from Hyperpolyglot
a side-by-side reference sheet
mathematica | maxima | pari/gp | |
---|---|---|---|
version used | 8.0 | 5.21 | 2.3 |
show version | select About Mathematica in Mathematica menu | $ maxima --version | $ gp --version |
grammar and invocation | |||
mathematica | maxima | pari/gp | |
interpreter | $ maxima -b foo.mac | $ gp -q foo.gp | |
repl | $ math | $ maxima | $ gp |
block delimiters | ( stmt; …) | block ( … ) | { … } |
statement separator | ; or sometimes newline ; before a newline suppresses output | ; suppresses output: $ | newline or ; a trailing semicolon suppresses output |
end-of-line comment | none | none | 1 + 1 \\ addition |
multiple line comment | 1 + (* addition *) 1 | 1 + /* addition */ 1 | 1 + /* addition */ 1 |
variables and expressions | |||
mathematica | maxima | pari/gp | |
assignment | a = 3 Set[a, 3] | a: 3 | a = 3 |
parallel assignment | {a, b} = {3, 4} Set[{a, b}, {3, 4}] | [a, b]: [3, 4] | none |
compound assignment | += -= *= /= corresponding functions: AddTo SubtractFrom TimeBy DivideBy | none | += -= *= /= %= |
increment and decrement | ++x --x PreIncrement[x] PreDecrement[x] x++ x-- Increment[x] Decrement[x] | none | return value after increment or decrement: x++ x-- |
null | Null | ||
null test | |||
undefined variable access | treated as an unknown number | treated as an unknown symbol | treated as an unknown number |
remove variable binding | Clear[x] Remove[x] | kill(x) | kill(x) |
conditional expression | If[x > 0, x, -x] | if is(x > 0) then x else -x | if(x > 0, x, -x) |
arithmetic and logic | |||
mathematica | maxima | pari/gp | |
true and false | True False | true false | 1 0 |
falsehoods | False | false | 0 |
logical operators | ! True || (True && False) Or[Not[True], And[True, False]] | is(not true or (true and false)) | ! 1 || (1 && 0) |
relational operators | == != > < >= <= corresponding functions: Equal Unequal Greater Less GreaterEqual LessEqual | = # > < >= <= | == != > < >= <= |
arithmetic operators | + - * / Quotient Mod adjacent terms are multiplied, so * is not necessary. Quotient and Mod are functions, not binary infix operators. These functions are also available: Plus Subtract Times Divide | + - * / quotient mod quotient and mod are functions, not binary infix operators | + - * / none % |
integer division | Quotient[a, b] | quotient(a, b) | divrem(a, b)[1] |
integer division by zero | dividend is zero: Indeterminate otherwise: ComplexInfinity | error | error |
float division | exact division: a / b | float(a) / b | exact division: a / b |
float division by zero | dividend is zero: Indeterminate otherwise: ComplexInfinity | error | error |
power | 2 ^ 16 Power[2, 16] | 2 ^ 16 | 2 ^ 16 |
sqrt | returns symbolic expression: Sqrt[2] | returns symbolic expression: sqrt(2) | returns float: sqrt(2) |
sqrt -1 | I | %i | 1.000 * I |
transcendental functions | Exp Log Sin Cos Tan ArcSin ArcCos ArcTan ArcTan ArcTan accepts 1 or 2 arguments | exp log sin cos tan asin acos atan atan2 | exp log sin cos tan asin acos atan none |
transcendental constants pi and the euler constant | Pi E | %pi %e | Pi exp(1) |
float truncation round towards zero, round to nearest integer, round down, round up | IntegerPart Round Floor Ceiling | truncate round floor ceiling | truncate round floor ceil |
absolute value and signum | Abs Sign | abs sign | abs sign |
integer overflow | none, has arbitrary length integer type | none, has arbitrary length integer type | none, has arbitrary length integer type |
float overflow | none | error | error |
rational construction | use integer division: 1 / 7 | use integer division: 1 / 7 | use integer division: 1 / 7 |
rational decomposition | Numerator Denominator | ratnumer ratdenom | numerator denominator |
complex construction | 1 + 3I | 1 + 3 * %i | 1 + 3 * I |
complex decomposition real and imaginary part, argument and modulus, conjugate | Re Im Arg Abs Conjugate | realpart imagpart carg abs conjugate | real imag ?? abs conj |
random number uniform integer, uniform float | RandomInteger[{0, 99}] RandomReal[] | random(100) random(1.0) | random(100) ?? |
random seed set, get | SeedRandom[17] ?? | set_random_state(make_random_state(17)); ?? | setrand(17) getrand() |
binary, octal, and hex literals | 2^^101010 8^^52 16^^2a | ||
base conversion | BaseForm[42, 7] BaseForm[7^^60, 10] | \\ 42 as powers of 7 up to 9th power: 42 + O(7^10) | |
strings | |||
mathematica | maxima | pari/gp | |
string literals | "don't say \"no\"" | "don't say \"no\"" | "don't say \"no\"" |
newline in literal | yes | no; use \n escape | |
string literal escapes | \\ \" \b \f \n \r \t \ooo | \n \t \" \\ | |
character access | Characters["hello"][[1]] | charat("hello", 1) | |
chr and ord | FromCharacterCode[{65}] ToCharacterCode["A"][[1]] | ||
length | StringLength["hello"] | slength("hello") | length("hello") |
concatenate | "one " <> "two " <> "three" | concat("one", "two", "three"); | Str("one", "two", "three") |
index of substring | StringPosition["hello", "el"][[1]][[1]] StringPosition returns an array of pairs, one for each occurrence of the substring. Each pair contains the index of the first and last character of the occurrence. | ssearch("el", "hello") counts from one, returns false if not found | |
extract substring | StringTake["hello", {1, 4}] | substring("hello", 1, 5) | |
split | StringSplit["foo,bar,baz", ","] | split("foo,bar,baz",",") | |
join | StringJoin[Riffle[{"foo", "bar", "baz"}, ","]] | simplode(["foo","bar","baz"],",") | |
trim | StringTrim[" foo "] | strim(" ", " foo ") striml(" ", " foo") strimr(" ", "foo ") | |
convert from string, to string | 7 + ToExpression["12"] 73.9 + ToExpression[".037"] "value: " <> ToString[8] | 7 + parse_string("12") 73.9 + parse_string(".037") | |
case manipulation | ToUpperCase["foo"] ToLowerCase["FOO"] | supcase("foo") sdowncase("FOO") | |
regular expressions | |||
mathematica | maxima | pari/gp | |
regex test | re = RegularExpression["[a-z]+"] sc = StringCases["hello", re] Length[sc] > 0 | ||
regex substitution | s = "foo bar bar" re = RegularExpression["bar"] StringReplace[s, re -> "baz", 1] StringReplace[s, re -> "baz"] | ||
arrays | |||
mathematica | maxima | pari/gp | |
literal | {1, 2, 3} List[1, 2, 3] | [1, 2, 3] | \\ [1, 2, 3] is a vector literal: List([1, 2, 3]) |
size | Length[{1, 2, 3}] | length([1, 2, 3]) | length(List([1, 2, 3])) |
empty test | Length[{}] == 0 | emptyp([]); | length(List([])) == 0 |
lookup | (* access time is O(1) *) (* indices start at one: *) {1, 2, 3}[[1]] Part[{1, 2, 3}, 1] | /* access time is O(n) */ /* indices start at one: */ [1, 2, 3][1]; | \\ access time is O(1). \\ indices start at one: List([1, 2, 3])[1] |
update | a[[1]] = 7 | a[1]: 7; | listput(a, 7, 1) |
out-of-bounds behavior | left as unevaluated Part[] expression | invalid index error | out of allowed range error |
element index | (* returns list of all positions: *) First /@ Position[{7, 8, 9, 9}, 9] | /* returns list of all positions: */ sublist_indices([7, 8, 9, 9], lambda([x], x = 9)); | none |
slice | {1, 2, 3}[[1 ;; 2]] | none | none |
array of integers as index | (* evaluates to {7, 9, 9} *) {7, 8, 9}[[{1, 3, 3}]] | none | none |
manipulate back | a = {6,7,8} AppendTo[a, 9] elem = a[[Length[a]]] a = Delete[a, Length[a]] elem | a: [6, 7, 8]; a: endcons(9, a); last(a); /* no easy way to delete last element */ | a = List([6, 7, 8]) listput(a, 9) elem = listpop(a) |
manipulate front | a = {6,7,8} PrependTo[a, 5] elem = a[[1]] a = Delete[a, 1] elem | load("basic"); a: [6, 7, 8]; push(5, a); elem: pop(a); | a = List([6, 7, 8]); listinsert(a, 5, 1); elem = a[1]; listpop(a, 1); |
head | First[{1, 2, 3}] | first([1, 2, 3]); | List([1, 2, 3])[1] |
tail | Rest[{1, 2, 3}] | rest([1, 2, 3]); | none |
cons | (* first arg must be an array *) Prepend[{2, 3}, 1] | /* second arg must be an array */ cons(1, [2, 3]); | a = List([1, 2, 3]); listinsert(a, 1, 1); |
concatenate | Join[{1, 2, 3}, {4, 5, 6}] | append([1, 2, 3], [4, 5, 6]) | concat(List([1, 2, 3]), List([4, 5, 6])) |
replicate | ten_zeros = Table[0, {i, 0, 9}] | ten_zeros: makelist(0, 10); | |
copy | a2 = a | a2: copylist(a); | a2 = a |
iterate | Function[x, Print[x]] /@ {1, 2, 3} | a: [1, 2, 3]; for i from 1 thru length(a) do print(a[i]); | a = List([1, 2, 3]) for(i=1, length(a), print(a[i])) |
reverse | Reverse[{1, 2, 3}] | reverse([1, 2, 3]); | a = List([1, 2, 3]) a2 = listcreate() while(i > 0, listput(a2, a[i]); i—) |
sort | Sort[{3, 1, 4, 2}] | sort([3, 1, 4, 2]); | a = List([3,1,4,2]) listsort(a) a |
dedupe | Union[{1, 2, 2, 3}] | unique([1, 2, 2, 3]); | |
membership | MemberQ[{1, 2, 3}, 2] | member(2, [1, 2, 3]); | /* The Set() constructor takes an array or vector as an argument. It converts the elements to strings and sorts them, discarding duplicates. setsearch() returns the index of the element or zero if not in the set. */ setsearch(Set([1, 2, 3]), 2) |
intersection | Intersect[{1, 2}, {2, 3, 4}] | /* { } is literal notation for a set; use setify() to convert array to set */ intersect({1, 2}, {2, 3, 4}); | setintersect(Set([1, 2]), Set([2, 3, 4])) |
union | Union[{1, 2}, {2, 3, 4}] | union({1, 2}, {2, 3, 4}); | setunion(Set([1, 2]), Set([2, 3, 4])) |
relative complement, symmetric difference | Complement[{1, 2, 3}, {2}] none | setdifference({1, 2, 3}, {2}); symmdifference({1, 2}, {2, 3, 4}); | setminus(Set([1, 2, 3]), Set([2])) |
map | Function[x, x x] /@ {1, 2, 3} Map[Function[x, x x], {1, 2, 3}] | map(lambda([x], x * x), [1, 2, 3]) | |
filter | Select[{1, 2, 3}, # > 2 &] | sublist([1, 2, 3], lambda([x], x > 2)) | |
reduce | Fold[Plus, 0, {1, 2, 3}] | /* returns -4: */ lreduce(lambda([x,y], x - y), [1, 2, 3]) /* returns 2: */ rreduce(lambda([x,y], x - y), [1, 2, 3]) | |
universal and existential tests | none | every(evenp, [1, 2, 3]); some(evenp, [1, 2, 3]); | |
min and max element | Min[{1, 2, 3}] Max[{1, 2, 3}] | apply(min, [1, 2, 3]); apply(max, [1, 2, 3]); | |
shuffle and sample | x = {3, 7, 5, 12, 19, 8, 4} RandomSample[x] RandomSample[x, 3] | random_permutation([3, 7, 5, 12, 19, 8, 4]); | |
zip | (* list of six elements: *) Riffle[{1, 2, 3}, {"a", "b", "c"}] | /* list of six elements: */ join([1, 2, 3], ["a", "b", "c"]) | |
sequences | |||
mathematica | maxima | pari/gp | |
range | Range[1, 100] | makelist(i, i, 1, 100) | |
arithmetic sequence of integers with difference 10 | Range[1, 100, 10] | ||
arithmetic sequence of floats with difference 0.1 | Range[1, 100, .1] | ||
multidimensional-arrays | |||
mathematica | maxima | pari/gp | |
dictionaries | |||
mathematica | maxima | pari/gp | |
record literal | r = { n -> 10, avg -> 3.7, sd -> 0.4} | defstruct(point(x, y, z)); p: point(2, 3, 5); | |
record member access | n /. r | p@x | |
functions | |||
mathematica | maxima | pari/gp | |
definition | add[a_, b_] := a + b (* alternate syntax: *) add = Function[{a, b}, a + b] | add(a, b) := a + b; | add(x, y) = x + y |
invocation | add[3, 7] add @@ {3, 7} | add(3, 7); | add(3, 7) |
return value | |||
function value | |||
anonymous function | Function[{a, b}, a + b] (#1 + #2) & | lambda([a, b], a + b) | |
missing argument | error | ||
extra argument | error | ||
default argument | |||
variable number of arguments | f(x, [L]) := if emptyp(L) then x else [x, apply("+", L)]; f(1); f(1, 2, 3); | ||
execution control | |||
mathematica | maxima | pari/gp | |
if | If[x > 0, Print["positive"], If[x < 0, Print["negative"], Print["zero"]]] | if (is(x > 0)) then print("positive") elseif (is(x < 0)) then print("negative") else print("zero") | if(x > 0, \ print("positive"), \ if(x < 0, \ print("negative"), \ print("zero"))) |
while | i = 0 While[i < 10, Print[i]; i++] | i = 0 while(i < 10, print(i); i++) | |
for | For[i = 0, i < 10, i++, Print[i]] | for i from 0 thru 9 do print(i); | for(i=0, 9, print(i)) |
break/continue | Break[] Continue[] | break continue | |
raise exception | Throw["failed"] | throw("failed"); error("failed"); | error("failed") |
handle exception | Print[Catch[Throw["failed"]]] | catch(throw("failed")); errcatch(error("failed")); | |
finally block | none | ||
files | |||
mathematica | maxima | pari/gp | |
write to stdout | Print["hello"] | print("hello") | print("hello") |
read entire file into string or array | s = Import["/etc/hosts"] a = StringSplit[s, "\n"] | ||
redirect to file | |||
libraries and namespaces | |||
mathematica | maxima | pari/gp | |
load | |||
reflection | |||
mathematica | maxima | pari/gp | |
list function documentation | ?? | ? | |
get function documentation | ?Tan Information[Tan] | ? tan describe(tan) | ? tan |
grep documentation | ?? tan | ||
query data type | Head[x] | bigfloatp(x) floatnump(x) integerp(x) numberp(x) ratnump(x) stringp(x) listp(x) | type(x) |
list variables in scope | ? 0 | ||
algebra | |||
mathematica | maxima | pari/gp | |
solution to an equation | Solve[x^3 + x + 3 == 0, x] | solve(x^3 + x + 3, x) | |
solution to two equations | Solve[x + y == 3 && x == 2y, {x, y}] | solve([x+y=3, x=2*y], [x, y]) | |
numerical approximation | N[Exp[1]] Exp[1] + 0. N[Exp[1], 10] | float(exp(1)) | 1/7 + 0. |
expand polynomial | Expand[(1 + x)^5] | expand((1+x)^5) | |
factor polynomial | Factor[3 + 10 x + 9 x^2 + 2 x^3] | factor(3 + 10*x + 9*x^2 + 2*x^3) | |
add fractions | Together[a/b + c/d] | ratsimp(a/b + c/d) | |
decompose fraction | Apart[(b c + a d)/(b d)] | ||
calculus | |||
mathematica | maxima | pari/gp | |
differentation | D[x^3 + x + 3, x] | diff(x^3 + x + 3, x) diff(sin(x), x) | P = x^3 + x + 3 P' sin(x)' |
higher order differentiation | D[Log[x], {x, 3}] | diff(log(x), x, 3); | |
integration | Integrate[x^3 + x + 3, x] Integrate[x^3 + x + 3, {x, 0, 1}] | integrate(x^3 + 3*x + 3, x); integrate(x^3 + 3*x + 3, x, 0, 1); | |
find minimal value | Minimize[Sqrt[a^2 + x^2] + Sqrt[(b - x)^2 + c^2], x] | ||
number theory | |||
mathematica | maxima | pari/gp | |
number tests | IntegerQ[7] PrimeQ[7] rational test? real test? | integerp(7) primep(7) ratnump(1/7) | |
solve diophantine equation | Solve[a^2 + b^2 == c^2 && a > 0 && a < 10 && b > 0 && b < 10 && c > 0 && c < 10, {a, b, c}, Integers] | ||
factorial | 10! | 10! | 10! |
binomial coefficient | Binomial[10,3] | binomial(10,3) | |
greatest common divisor | GCD[14, 21] | gcd(14, 21) | gcd(14, 21) |
prime factors | returns {{2, 2}, {3, 1}, {7, 1}} FactorInteger[84] | factor(84) | returns [2,2; 3,1; 7,1] factor(84) |
Euler totient | EulerPhi[256] | totient(256) | |
vectors | |||
mathematica | maxima | pari/gp | |
vector literal | (* same as array: *) {1, 2, 3} | /* same as list: */ [1, 2, 3] | [1, 2, 3] |
vector coordinate | indices start at one: {1,v2, 3}[[1]] | indices start at one: [1, 2, 3][1] | indices start at one: [1, 2, 3][1] |
vector dimension | Length[{1, 2, 3}] | length([1, 2, 3]) | length([1, 2, 3]) |
element-wise arithmetic operators | + - * / adjacent lists are multiplied element-wise | + - * / | + - |
vector length mismatch | error | error | error |
scalar multiplication | 3 {1, 2, 3} {1, 2, 3} 3 * may also be used | 3 * [1, 2, 3] [1, 2, 3] * 3 | 3 * [1, 2, 3] [1, 2, 3] * 3 |
dot product | {1, 1, 1} . {2, 2, 2} Dot[{1, 1, 1}, {2, 2, 2}] | [1,1,1] . [2,2,2] | |
cross product | Cross[{1, 0, 0}, {0, 1, 0}] | load("vect"); express([1, 0, 0] ~ [0, 1, 0]); | |
norms | Norm[{1, 2, 3}, 1] Norm[{1, 2, 3}] Norm[{1, 2, 3}, Infinity] | ||
matrices | |||
mathematica | maxima | pari/gp | |
literal or constructor | A = {{1, 2}, {3, 4}} B = {{4, 3}, {2, 1}} | A: matrix([1, 2], [3, 4]); B: matrix([4, 3], [2, 1]); | A = [1, 2; 3, 4] B = [4, 3; 2, 1] |
zero, identity, ones, diagonal matrix | ConstantArray[0, {3, 3}] IdentityMatrix[3] ConstantArray[1, {3, 3}] DiagonalMatrix[{1, 2, 3}] | zeromatrix(3, 3) ident(3) 1 + zeromatrix(3, 3) diag_matrix(1, 2, 3) | |
dimensions rows, columns | Length[A] Length[A[[1]]] | matrix_size(A)[1] matrix_size(A)[2] | |
element access | A[[1, 1]] | A[1, 1] | A[1, 1] |
row access | A[[1]] | as list: A[1] as 1xn matrix: row(A, 1) | |
column access | col(A, 1) | ||
submatrix access | # [[1]] & /@ A | ||
scalar multiplication | 3 A A 3 * can also be used | 3 * A A * 3 | |
element-wise operators | + - * / adjacent matrices are multiplied element-wise | + - * / | |
multiplication | A . B | A . B | |
kronecker product | KroneckerProduct[A, B] | kronecker_product(A, B); | |
comparison | A == B A != B | is(A = B) is(A # B) | |
norms | Norm[A, 1] Norm[A] Norm[A, Infinity] Norm[A, "Frobenius"] | ||
transpose | Transpose[A] | ||
conjugate transpose | A = {{I, 2 I}, {3 I, 4 I}} ConjugateTranspose[A] | ||
inverse | Inverse[A] | ||
determinant | Det[A] | matdet(A) | |
trace | Tr[A] | trace(A) | |
eigenvalues | Eigenvalues[A] | ||
eigenvectors | Eigenvectors[A] | ||
system of equations | Solve[A. {x, y} == { 2, 3}, {x, y}] | ||
distributions | |||
mathematica | maxima | pari/gp | |
normal | nd = NormalDistribution[0,1] RandomVariate[nd] | load(distrib); random_normal(0,1); | |
exponential | ed = ExponentialDistribution[1] RandomVariate[ed] | load(distrib); random_exp(1); | |
poisson | pd = PoissonDistribution[1] RandomVariate[pd] | load(distrib); random_poisson(1); | |
univariate charts | |||
mathematica | maxima | pari/gp | |
vertical bar chart | BarChart[{7, 3, 8, 5, 5}, ChartLegends-> {"a","b","c","d","e"}] | ||
horizontal bar chart | BarChart[{7, 3, 8, 5, 5}, BarOrigin -> Left] | ||
pie chart | PieChart[{7, 3, 8, 5, 5}] | ||
stem-and-leaf plot | Needs["StatisticalPlots`"] nd = NormalDistribution[0, 1] n100 = RandomVariate[nd, 100] StemLeafPlot[20 * n100] | ||
histogram | nd = NormalDistribution[0, 1] Histogram[RandomReal[nd, 100], 10] | ||
box-and-whisker plot | nd = NormalDistribution[0, 1] n100 = RandomVariate[nd, 100] BoxWhiskerChart[d] ed = ExponentialDistribution[1] e100 = RandomVariate[ed, 100] u100 = RandomReal[1, 100] d = {n100, e100, u100} BoxWhiskerChart[d] | ||
set chart title | BoxWhiskerChart[data, PlotLabel -> "chart example"] | ||
chart options | PlotLabel -> "an example" AxisLabel -> {"time", "distance"} | ||
bivariate charts | |||
mathematica | maxima | pari/gp | |
stacked bar chart | d = {{7, 1}, {3, 2}, {8, 1}, {5, 3}, {5, 1}} BarChart[d, ChartLayout -> "Stacked"] | ||
scatter plot | nd = NormalDistribution[0, 1] rn = Function[RandomReal[nd]] d = {rn[],rn[]} & /@ Range[1,50] ListPlot[d] | ||
linear regression line | d = Table[{i, 2 i + RandomReal[{-5, 5}]}, {i, 0, 20}] model = LinearModelFit[d, x, x] Show[ListPlot[d], Plot[model["BestFit"], {x, 0, 20}]] | ||
polygonal line plot | f = Function[i, {i, rn[]}] d = f /@ Range[1, 20] ListLinePlot[d] | ||
area chart | d = {{7, 1, 3, 2, 8}, {1, 5, 3, 5, 1}} sd = {d[[1]], d[[1]] + d[[2]]} ListLinePlot[sd, Filling -> {1 -> {Axis, LightBlue}, 2 -> {{1}, LightRed}}] | ||
cubic spline | d = Table[{i, RandomReal[nd]}, {i, 0, 20}] f = Interpolation[d, InterpolationOrder -> 3] Show[ListPlot[d], Plot[f[x], {x, 0, 20}]] | ||
function plot | Plot[Sin[x], {x, -4, 4}] | plot2d(sin(x),[x,-4,4]); | ploth(x=-4, 4, sin(x)) |
quantile-quantile plot | nd = NormalDistribution[0, 1] d1 = RandomReal[1, 50] d2 = RandomReal[nd, 50] QuantilePlot[d1, d2] | ||
axis label | d = Table[{i, i^2}, {i, 1, 20}] ListLinePlot[d, AxesLabel -> {x, x^2}] | plot2d(sin(x), [x,-4,4], [ylabel,"sine function"]); | |
logarithmic y-axis | LogPlot[{x^2, x^3, x^4, x^5}, {x, 0, 20}] | ||
trivariate charts | |||
mathematica | maxima | pari/gp | |
3d scatter plot | nd = NormalDistribution[0,1] d = RandomReal[nd, {50, 3}] ListPointPlot3D[d] | ||
additional data set | nd = NormalDistribution[0, 1] x1 = RandomReal[nd, 20] x2 = RandomReal[nd, 20] ListLinePlot[{x1, x2}] | ||
bubble chart | nd = NormalDistribution[0,1] d = RandomReal[nd, {50, 3}] BubbleChart[d] | ||
surface plot | Plot3D[Sinc[Sqrt[x^2 + y^2]], {x, -25, 25}, {y, -25, 25}] | sinc(x) := sin(%pi*x)/(%pi*x);sinc(x) := sin(%pi*x)/(%pi*x); plot3d(sinc(sqrt(x^2+y^2)),[x,-25,25],[y,-25,25]); | |
______________________________________________________ | ______________________________________________________ | ______________________________________________________ |
version used
The version of software used to check the examples in the reference sheet.
show version
How to determine the version of an installation.
Grammar and Invocation
interpreter
How to execute a script.
pari/gp
The shebang style notation doesn't work because GP doesn't recognize the hash tag # as the start of a comment.
The -q option suppresses the GP startup message.
After the script finishes it will drop the user into the REPL unless there is a quit statement in the script:
print("Hello, World!")
quit
repl
How to launch a command line read-eval-print loop for the language.
mathematica:
One can create a REPL called math on Mac OS X with the following command:
$ sudo ln -s /Applications/Mathematica.app/Contents/MacOS/MathKernel /usr/local/bin/math
$ math
block delimiters
How blocks are delimited.
statement separator
How statements are separated.
end-of-line comment
Character used to start a comment that goes to the end of the line.
multiple line comment
Variables and Expressions
assignment
How to perform assignment.
In all three languages an assignment is an expression that evaluates to the right side of the expression. Assignments can be chained to assign the same value to multiple variables.
mathematica:
The Set function behaves identically to assignment and can be nested:
Set[a, Set[b, 3]]
parallel assignment
How to assign values in parallel.
Parallel assignment can be used to swap the values held in two variables.
compound assignment
The compound assignment operators.
increment and decrement
null
null test
How to test if a value is null.
undefined variable access
remove variable binding
How to remove a variable. Subsequent references to the variable will be treated as if the variable were undefined.
conditional expression
Arithmetic and Logic
true and false
The boolean literals.
falsehoods
Values which evaluate to false in a conditional test.
logical operators
The boolean operators.
relational operators
The relational operators.
arithmetic operators
The arithmetic operators.
integer division
How to compute the quotient of two integers.
integer division by zero
The result of dividing an integer by zero.
float division
How to perform float division, even if the arguments are integers.
float division by zero
The result of dividing a float by zero.
power
How to compute exponentiation.
Note that zero to a negative power is equivalent to division by zero, and negative numbers to a fractional power may have multiple complex solutions.
sqrt
The square root function.
For positive arguments the positive square root is returned.
sqrt -1
How the square root function handles negative arguments.
mathematica:
An uppercase I is used to enter the imaginary unit, but Mathematica displays it as a lowercase i.
transcendental functions
The standard transcendental functions such as one might find on a scientific calculator.
The functions are the exponential (not to be confused with exponentiation), natural logarithm, sine, cosine, tangent, arcsine, arccosine, arctangent, and the two argument arctangent.
transcendental constants
The transcendental constants pi and e.
The transcendental functions can used to computed to compute the transcendental constants:
pi = acos(-1)
pi = 4 * atan(1)
e = exp(1)
float truncation
Ways to convert a float to a nearby integer.
absolute value
How to get the absolute value and signum of a number.
integer overflow
What happens when the value of an integer expression cannot be stored in an integer.
The languages in this sheet all support arbitrary length integers so the situation does not happen.
float overflow
What happens when the value of a floating point expression cannot be stored in a float.
rational construction
How to construct a rational number.
rational decomposition
How to extract the numerator and denominator from a rational number.
complex construction
How to construct a complex number.
complex decomposition
How to extract the real and imaginary part from a complex number; how to extract the argument and modulus; how to get the complex conjugate.
random number
How to generate a random integer or a random float.
random seed
How to set or get the random seed.
maxima:
The seed is set to a fixed value at start up.
pari/gip:
The seed is set to a fixed value at start up.
mathematica:
The seed is not set to the same value at start up.
binary, octal, and hex literals
Binary, octal, and hex integer literals.
mathematica:
The notation works for any base from 2 to 36.
Strings
string literals
newline in literal
character access
chr and ord
length
concatenate
index of substring
extract substring
split
convert from string, to string
How to convert strings to numbers and vice versa.
join
trim
case manipulation
sprintf
Regular Expressions
regex test
How to test whether a string matches a regular expression.
regex substitution
How to replace substrings which match a regular expression.
Arrays
literal
The notation for an array literal.
size
The number of elements in the array.
empty test
How to test whether an array is empty.
lookup
How to access an array element by its index.
update
How to change the value stored at an array index.
out-of-bounds behavior
What happens when an attempt is made to access an element at an out-of-bounds index.
element index
How to get the index of an element in an array.
slice
How to extract a subset of the elements. The indices for the elements must be contiguous.
array of integers as index
manipulate back
manipulate front
head
tail
cons
concatenate
replicate
copy
How to copy an array. Updating the copy will not alter the original.
iterate
reverse
sort
dedupe
membership
How to test whether a value is an element of a list.
intersection
How to to find the intersection of two lists.
union
How to find the union of two lists.
relative complement, symmetric difference
How to find all elements in one list which are not in another; how to find all elements which are in one of two lists but not both.
map
filter
reduce
universal and existential tests
min and max element
shuffle and sample
How to shuffle an array. How to extract a random sample from an array without replacement.
zip
Sequences
Multidimensional Arrays
Dictionaries
record literal
record member access
Functions
definition
invocation
function value
Execution Control
if
How to write a branch statement.
mathematica:
The 3rd argument (the else clause) of an If expression is optional.
while
How to write a conditional loop.
mathematica:
Do can be used for a finite unconditional loop:
Do[Print[foo], {10}]
for
How to write a C-style for statement.
break/continue
How to break out of a loop. How to jump to the next iteration of a loop.
raise exception
How to raise an exception.
handle exception
How to handle an exception.
finally block
How to write code that executes even if an exception is raised.
Files
Libraries and Namespaces
Reflection
function documentation
How to get the documentation for a function.
Algebra
Calculus
Number Theory
Vectors
vector literal
The notation for a vector literal.
vector coordinate
How to get one of the coordinates of a vector.
vector dimension
How to get the number of coordinates of a vector.
element-wise arithmetic operators
How to perform an element-wise arithmetic operatio on vectors.
vector length mismatch
What happens when an element-wise arithmetic operation is performed on vectors of different dimension.
scalar multiplication
How to multiply a scalar with a vector.
dot product
How to compute the dot product of two vectors.
cross product
How to compute the cross product of two three-dimensional vectors.
norms
How to compute the norm of a vector.
Matrices
literal or constructor
Literal syntax or constructor for creating a matrix.
mathematica:
Matrices are represented as lists of lists. No error is generated if one of the rows contains too many or two few elements. The MatrixQ predicate can be used to test whether a list of lists is matrix: i.e. all of the sublists contain numbers and are of the same length.
Matrices are displayed by Mathematica using list notation. To see a matrix as it would be displayed in mathematical notation, use the MatrixForm function.
dimensions
How to get the dimensions of a matrix.
element access
How to access an element of a matrix. All languages described here follow the convention from mathematics of specifying the row index before the column index.
row access
How to access a row.
column access
How to access a column.
submatrix access
How to access a submatrix.
scalar multiplication
How to multiply a matrix by a scalar.
element-wise operators
Operators which act on two identically sized matrices element by element. Note that element-wise multiplication of two matrices is used less frequently in mathematics than matrix multiplication.
multiplication
How to multiply matrices. Matrix multiplication should not be confused with element-wise multiplication of matrices. Matrix multiplication in non-commutative and only requires that the number of columns of the matrix on the left match the number of rows of the matrix. Element-wise multiplication, by contrast, is commutative and requires that the dimensions of the two matrices be equal.
kronecker product
The Kronecker product is a non-commutative operation defined on any two matrices. If A is m x n and B is p x q, then the Kronecker product is a matrix with dimensions mp x nq.
comparison
How to test two matrices for equality.
norms
How to compute the 1-norm, the 2-norm, the infinity norm, and the frobenius norm.
Distributions
univariate-charts Univariate Charts
A univariate chart can be used to display a list or array of numerical values. Univariate data can be displayed in a table with a single column or two columns if each numerical value is given a name. A multivariate chart, by contrast, is used to display a list or array of tuples of numerical values.
In order for a list of numerical values to be meaningfully displayed in a univariate chart, it must be meaningful to perform comparisons (<, >, =) on the values. Hence the values should have the same unit of measurement.
vertical bar chart
A chart which represents values with rectangular bars which line up on the bottom. It is a deceptive practice for the bottom not to represent zero, even if a y-axis with labelled tick marks or grid lines is provided. A cut in the vertical axis and one of the bars may be desirable if the cut value is a large outlier. Putting such a cut all of the bars near the bottom is a deceptive practice similar not taking to the base of the bars to be zero, however.
Another bad practice is the 3D bar chart. In such a chart heights are represented by the height of what appear to be three dimensional blocks. Such charts impress an undiscriminating audience but make it more difficult to make a visual comparison of the charted quantities.
mathematica
horizontal bar chart
A bar chart in which zero is the y-axis and the bars extend to the right.
pie chart
A bar chart displays values using the areas of circular sectors or equivalently, the lengths of the arcs of those sectors. A pie chart implies that the values are percentages of a whole. The viewer is likely to make an assumption about what the whole circle represents. Thus, using a pie chart to show the revenue of some companies in a line of business could be regarded as deceptive if there are other companies in the same line of business which are left out. The viewer may mistakenly assume the whole circle represents the total market.
If two values are close in value, people cannot determine visually which of the corresponding sectors in a pie chart is larger without the aid of a protractor. For this reason many consider bar charts superior to pie charts.
Many software packages make 3D versions of pie charts which communicate no additional information and in fact make it harder to interpret the data.
stem-and-leaf plot
histogram
box-and-whisker plot
set chart title
Bivariate Charts
stacked bar chart
Trivariate Charts
Mathematica
Mathematica Documentation Center
WolframAlpha
Maxima
Pari/GP
A Tutorial for Pari/GP (pdf)
Pari/GP Functions by Category
Pari/GP Reference Card (pdf)