Help
MATLAB/Octave |
Python |
Description |
doc help -i % browse with Info
|
help() |
Browse help interactively |
help help or doc doc
|
help |
Help on using help |
help plot |
help(plot) or ?plot
|
Help for a function |
help splines or doc splines
|
help(pylab) |
Help for a toolbox/library package |
demo |
|
Demonstration examples |
Searching available documentation
MATLAB/Octave |
Python |
Description |
lookfor plot |
|
Search help files |
help |
help(); modules [Numeric] |
List available packages |
which plot |
help(plot) |
Locate functions |
Using interactively
MATLAB/Octave |
Python |
Description |
octave -q |
ipython -pylab |
Start session |
TAB or M-? |
TAB |
Auto completion |
foo(.m) |
execfile('foo.py') or run foo.py
|
Run code from file |
history |
hist -n |
Command history |
diary on [..] diary off |
|
Save command history |
exit or quit
|
CTRL-D CTRL-Z # windows sys.exit()
|
End session |
Operators
MATLAB/Octave |
Python |
Description |
help - |
|
Help on operator syntax |
Arithmetic operators
MATLAB/Octave |
Python |
Description |
a=1; b=2; |
a=1; b=1 |
Assignment; defining a number |
a + b |
a + b or add(a,b)
|
Addition |
a - b |
a - b or subtract(a,b)
|
Subtraction |
a * b |
a * b or multiply(a,b)
|
Multiplication |
a / b |
a / b or divide(a,b)
|
Division |
a .^ b |
a ** b power(a,b) pow(a,b)
|
Power, $a^b$ |
rem(a,b) |
a % b remainder(a,b) fmod(a,b)
|
Remainder |
a+=1 |
a+=b or add(a,b,a)
|
In place operation to save array creation overhead |
factorial(a) |
|
Factorial, $n!$ |
Relational operators
MATLAB/Octave |
Python |
Description |
a == b |
a == b or equal(a,b)
|
Equal |
a < b |
a < b or less(a,b)
|
Less than |
a > b |
a > b or greater(a,b)
|
Greater than |
a <= b |
a <= b or less_equal(a,b)
|
Less than or equal |
a >= b |
a >= b or greater_equal(a,b)
|
Greater than or equal |
a ~= b |
a != b or not_equal(a,b)
|
Not Equal |
Logical operators
MATLAB/Octave |
Python |
Description |
a && b |
a and b |
Short-circuit logical AND |
a || b |
a or b |
Short-circuit logical OR |
a & b or and(a,b)
|
logical_and(a,b) or a and b
|
Element-wise logical AND |
a | b or or(a,b)
|
logical_or(a,b) or a or b
|
Element-wise logical OR |
xor(a, b) |
logical_xor(a,b) |
Logical EXCLUSIVE OR |
~a or not(a) ~a or !a
|
logical_not(a) or not a
|
Logical NOT |
any(a) |
|
True if any element is nonzero |
all(a) |
|
True if all elements are nonzero |
root and logarithm
MATLAB/Octave |
Python |
Description |
sqrt(a) |
math.sqrt(a) |
Square root |
log(a) |
math.log(a) |
Logarithm, base $e$ (natural) |
log10(a) |
math.log10(a) |
Logarithm, base 10 |
log2(a) |
math.log(a, 2) |
Logarithm, base 2 (binary) |
exp(a) |
math.exp(a) |
Exponential function |
Round off
MATLAB/Octave |
Python |
Description |
round(a) |
around(a) or math.round(a)
|
Round |
ceil(a) |
ceil(a) |
Round up |
floor(a) |
floor(a) |
Round down |
fix(a) |
fix(a) |
Round towards zero |
Mathematical constants
MATLAB/Octave |
Python |
Description |
pi |
math.pi |
$\pi=3.141592$ |
exp(1) |
math.e or math.exp(1)
|
$e=2.718281$ |
Missing values; IEEE-754 floating point status flags
MATLAB/Octave |
Python |
Description |
NaN |
nan |
Not a Number |
Inf |
inf |
Infinity, $\infty$ |
|
plus_inf |
Infinity, $+\infty$ |
|
minus_inf |
Infinity, $-\infty$ |
|
plus_zero |
Plus zero, $+0$ |
|
minus_zero |
Minus zero, $-0$ |
Complex numbers
MATLAB/Octave |
Python |
Description |
i |
z = 1j |
Imaginary unit |
z = 3+4i |
z = 3+4j or z = complex(3,4)
|
A complex number, $3+4i$ |
abs(z) |
abs(3+4j) |
Absolute value (modulus) |
real(z) |
z.real |
Real part |
imag(z) |
z.imag |
Imaginary part |
arg(z) |
|
Argument |
conj(z) |
z.conj(); z.conjugate() |
Complex conjugate |
Trigonometry
MATLAB/Octave |
Python |
Description |
atan(a,b) |
atan2(b,a) |
Arctangent, $\arctan(b/a)$ |
|
hypot(x,y) |
Hypotenus; Euclidean distance |
Generate random numbers
MATLAB/Octave |
Python |
Description |
rand(1,10) |
random.random((10,)) random.uniform((10,))
|
Uniform distribution |
2+5*rand(1,10) |
random.uniform(2,7,(10,)) |
Uniform: Numbers between 2 and 7 |
rand(6) |
random.uniform(0,1,(6,6)) |
Uniform: 6,6 array |
randn(1,10) |
random.standard_normal((10,)) |
Normal distribution |
Vectors
MATLAB/Octave |
Python |
Description |
a=[2 3 4 5]; |
a=array([2,3,4,5]) |
Row vector, $1 \times n$-matrix |
adash=[2 3 4 5]'; |
array([2,3,4,5])[:,NewAxis] array([2,3,4,5]).reshape(-1,1) r_[1:10,'c']
|
Column vector, $m \times 1$-matrix |
Sequences
MATLAB/Octave |
Python |
Description |
1:10 |
arange(1,11, dtype=Float) range(1,11)
|
1,2,3, ... ,10 |
0:9 |
arange(10.) |
0.0,1.0,2.0, ... ,9.0 |
1:3:10 |
arange(1,11,3) |
1,4,7,10 |
10:-1:1 |
arange(10,0,-1) |
10,9,8, ... ,1 |
10:-3:1 |
arange(10,0,-3) |
10,7,4,1 |
linspace(1,10,7) |
linspace(1,10,7) |
Linearly spaced vector of n=7 points |
reverse(a) |
a[::-1] or
|
Reverse |
a(:) = 3 |
a.fill(3), a[:] = 3 |
Set all values to same scalar value |
Concatenation (vectors)
MATLAB/Octave |
Python |
Description |
[a a] |
concatenate((a,a)) |
Concatenate two vectors |
[1:4 a] |
concatenate((range(1,5),a), axis=1) |
|
Repeating
MATLAB/Octave |
Python |
Description |
[a a] |
concatenate((a,a)) |
1 2 3, 1 2 3 |
|
a.repeat(3) or
|
1 1 1, 2 2 2, 3 3 3 |
|
a.repeat(a) or
|
1, 2 2, 3 3 3 |
Miss those elements out
MATLAB/Octave |
Python |
Description |
a(2:end) |
a[1:] |
miss the first element |
a([1:9]) |
|
miss the tenth element |
a(end) |
a[-1] |
last element |
a(end-1:end) |
a[-2:] |
last two elements |
Maximum and minimum
MATLAB/Octave |
Python |
Description |
max(a,b) |
maximum(a,b) |
pairwise max |
max([a b]) |
concatenate((a,b)).max() |
max of all values in two vectors |
[v,i] = max(a) |
v,i = a.max(0),a.argmax(0) |
|
Vector multiplication
MATLAB/Octave |
Python |
Description |
a.*a |
a*a |
Multiply two vectors |
dot(u,v) |
dot(u,v) |
Vector dot product, $u \cdot v$ |
Matrices
MATLAB/Octave |
Python |
Description |
a = [2 3;4 5] |
a = array([[2,3],[4,5]]) |
Define a matrix |
Concatenation (matrices); rbind and cbind
MATLAB/Octave |
Python |
Description |
[a ; b] |
concatenate((a,b), axis=0) vstack((a,b))
|
Bind rows |
[a , b] |
concatenate((a,b), axis=1) hstack((a,b))
|
Bind columns |
|
concatenate((a,b), axis=2) dstack((a,b))
|
Bind slices (three-way arrays) |
[a(:), b(:)] |
concatenate((a,b), axis=None) |
Concatenate matrices into one vector |
[1:4 ; 1:4] |
concatenate((r_[1:5],r_[1:5])).reshape(2,-1) vstack((r_[1:5],r_[1:5]))
|
Bind rows (from vectors) |
[1:4 ; 1:4]' |
|
Bind columns (from vectors) |
Array creation
MATLAB/Octave |
Python |
Description |
zeros(3,5) |
zeros((3,5),Float) |
0 filled array |
|
zeros((3,5)) |
0 filled array of integers |
ones(3,5) |
ones((3,5),Float) |
1 filled array |
ones(3,5)*9 |
|
Any number filled array |
eye(3) |
identity(3) |
Identity matrix |
diag([4 5 6]) |
diag((4,5,6)) |
Diagonal |
magic(3) |
|
Magic squares; Lo Shu |
|
a = empty((3,3)) |
Empty array |
Reshape and flatten matrices
MATLAB/Octave |
Python |
Description |
reshape(1:6,3,2)'; |
arange(1,7).reshape(2,-1) a.setshape(2,3)
|
Reshaping (rows first) |
reshape(1:6,2,3); |
arange(1,7).reshape(-1,2).transpose() |
Reshaping (columns first) |
a'(:) |
a.flatten() or
|
Flatten to vector (by rows, like comics) |
a(:) |
a.flatten(1) |
Flatten to vector (by columns) |
vech(a) |
|
Flatten upper triangle (by columns) |
Shared data (slicing)
MATLAB/Octave |
Python |
Description |
b = a |
b = a.copy() |
Copy of a |
Indexing and accessing elements (Python: slicing)
MATLAB/Octave |
Python |
Description |
a = [ 11 12 13 14 ... 21 22 23 24 ... 31 32 33 34 ]
|
a = array([[ 11, 12, 13, 14 ], [ 21, 22, 23, 24 ], [ 31, 32, 33, 34 ]])
|
Input is a 3,4 array |
a(2,3) |
a[1,2] |
Element 2,3 (row,col) |
a(1,:) |
a[0,] |
First row |
a(:,1) |
a[:,0] |
First column |
a([1 3],[1 4]); |
a.take([0,2]).take([0,3], axis=1) |
Array as indices |
a(2:end,:) |
a[1:,] |
All, except first row |
a(end-1:end,:) |
a[-2:,] |
Last two rows |
a(1:2:end,:) |
a[::2,:] |
Strides: Every other row |
|
a[...,2] |
Third in last dimension (axis) |
a(:,[1 3 4]) |
a.take([0,2,3],axis=1) |
Remove one column |
|
a.diagonal(offset=0) |
Diagonal |
Assignment
MATLAB/Octave |
Python |
Description |
a(:,1) = 99 |
a[:,0] = 99 |
|
a(:,1) = [99 98 97]' |
a[:,0] = array([99,98,97]) |
|
a(a>90) = 90; |
(a>90).choose(a,90) a.clip(min=None, max=90)
|
Clipping: Replace all elements over 90 |
|
a.clip(min=2, max=5) |
Clip upper and lower values |
Transpose and inverse
MATLAB/Octave |
Python |
Description |
a' |
a.conj().transpose() |
Transpose |
a.' or transpose(a)
|
a.transpose() |
Non-conjugate transpose |
det(a) |
linalg.det(a) or
|
Determinant |
inv(a) |
linalg.inv(a) or
|
Inverse |
pinv(a) |
linalg.pinv(a) |
Pseudo-inverse |
norm(a) |
norm(a) |
Norms |
eig(a) |
linalg.eig(a)[0] |
Eigenvalues |
svd(a) |
linalg.svd(a) |
Singular values |
chol(a) |
linalg.cholesky(a) |
Cholesky factorization |
[v,l] = eig(a) |
linalg.eig(a)[1] |
Eigenvectors |
rank(a) |
rank(a) |
Rank |
Sum
MATLAB/Octave |
Python |
Description |
sum(a) |
a.sum(axis=0) |
Sum of each column |
sum(a') |
a.sum(axis=1) |
Sum of each row |
sum(sum(a)) |
a.sum() |
Sum of all elements |
|
a.trace(offset=0) |
Sum along diagonal |
cumsum(a) |
a.cumsum(axis=0) |
Cumulative sum (columns) |
Sorting
MATLAB/Octave |
Python |
Description |
a = [ 4 3 2 ; 2 8 6 ; 1 4 7 ] |
a = array([[4,3,2],[2,8,6],[1,4,7]]) |
Example data |
sort(a(:)) |
a.ravel().sort() or
|
Flat and sorted |
sort(a) |
a.sort(axis=0) or msort(a)
|
Sort each column |
sort(a')' |
a.sort(axis=1) |
Sort each row |
sortrows(a,1) |
a[a[:,0].argsort(),] |
Sort rows (by first row) |
|
a.ravel().argsort() |
Sort, return indices |
|
a.argsort(axis=0) |
Sort each column, return indices |
|
a.argsort(axis=1) |
Sort each row, return indices |
Maximum and minimum
MATLAB/Octave |
Python |
Description |
max(a) |
a.max(0) or amax(a [,axis=0])
|
max in each column |
max(a') |
a.max(1) or amax(a, axis=1)
|
max in each row |
max(max(a)) |
a.max() or
|
max in array |
[v i] = max(a) |
|
return indices, i |
max(b,c) |
maximum(b,c) |
pairwise max |
cummax(a) |
|
|
|
a.ptp(); a.ptp(0) |
max-to-min range |
Matrix manipulation
MATLAB/Octave |
Python |
Description |
fliplr(a) |
fliplr(a) or a[:,::-1]
|
Flip left-right |
flipud(a) |
flipud(a) or a[::-1,]
|
Flip up-down |
rot90(a) |
rot90(a) |
Rotate 90 degrees |
repmat(a,2,3) kron(ones(2,3),a)
|
kron(ones((2,3)),a) |
Repeat matrix: [ a a a ; a a a ] |
triu(a) |
triu(a) |
Triangular, upper |
tril(a) |
tril(a) |
Triangular, lower |
Equivalents to "size"
MATLAB/Octave |
Python |
Description |
size(a) |
a.shape or a.getshape()
|
Matrix dimensions |
size(a,2) or length(a)
|
a.shape[1] or size(a, axis=1)
|
Number of columns |
length(a(:)) |
a.size or size(a[, axis=None])
|
Number of elements |
ndims(a) |
a.ndim |
Number of dimensions |
|
a.nbytes |
Number of bytes used in memory |
Matrix- and elementwise- multiplication
MATLAB/Octave |
Python |
Description |
a .* b |
a * b or multiply(a,b)
|
Elementwise operations |
a * b |
matrixmultiply(a,b) |
Matrix product (dot product) |
|
inner(a,b) or
|
Inner matrix vector multiplication $a\cdot b'$ |
|
outer(a,b) or
|
Outer product |
kron(a,b) |
kron(a,b) |
Kronecker product |
a / b |
|
Matrix division, $b{\cdot}a^{-1}$ |
a \ b |
linalg.solve(a,b) |
Left matrix division, $b^{-1}{\cdot}a$ \newline (solve linear equations) |
|
vdot(a,b) |
Vector dot product |
|
cross(a,b) |
Cross product |
Find; conditional indexing
MATLAB/Octave |
Python |
Description |
find(a) |
a.ravel().nonzero() |
Non-zero elements, indices |
[i j] = find(a) |
(i,j) = a.nonzero() (i,j) = where(a!=0)
|
Non-zero elements, array indices |
[i j v] = find(a) |
v = a.compress((a!=0).flat) v = extract(a!=0,a)
|
Vector of non-zero values |
find(a>5.5) |
(a>5.5).nonzero() |
Condition, indices |
|
a.compress((a>5.5).flat) |
Return values |
a .* (a>5.5) |
where(a>5.5,0,a) or a * (a>5.5)
|
Zero out elements above 5.5 |
|
a.put(2,indices) |
Replace values |
Multi-way arrays
MATLAB/Octave |
Python |
Description |
a = cat(3, [1 2; 1 2],[3 4; 3 4]); |
a = array([[[1,2],[1,2]], [[3,4],[3,4]]]) |
Define a 3-way array |
a(1,:,:) |
a[0,...] |
|
File input and output
MATLAB/Octave |
Python |
Description |
f = load('data.txt') |
f = fromfile("data.txt") f = load("data.txt")
|
Reading from a file (2d) |
f = load('data.txt') |
f = load("data.txt") |
Reading from a file (2d) |
x = dlmread('data.csv', ';') |
f = load('data.csv', delimiter=';') |
Reading fram a CSV file (2d) |
save -ascii data.txt f |
save('data.csv', f, fmt='%.6f', delimiter=';') |
Writing to a file (2d) |
|
f.tofile(file='data.csv', format='%.6f', sep=';') |
Writing to a file (1d) |
|
f = fromfile(file='data.csv', sep=';') |
Reading from a file (1d) |
Plotting
Basic x-y plots
MATLAB/Octave |
Python |
Description |
plot(a) |
plot(a) |
1d line plot |
plot(x(:,1),x(:,2),'o') |
plot(x[:,0],x[:,1],'o') |
2d scatter plot |
plot(x1,y1, x2,y2) |
plot(x1,y1,'bo', x2,y2,'go') |
Two graphs in one plot |
plot(x1,y1) hold on plot(x2,y2)
|
plot(x1,y1,'o') plot(x2,y2,'o') show() # as normal
|
Overplotting: Add new plots to current |
subplot(211) |
subplot(211) |
subplots |
plot(x,y,'ro-') |
plot(x,y,'ro-') |
Plotting symbols and color |
Axes and titles
MATLAB/Octave |
Python |
Description |
grid on |
grid() |
Turn on grid lines |
axis equal axis('equal') replot
|
figure(figsize=(6,6)) |
1:1 aspect ratio |
axis([ 0 10 0 5 ]) |
axis([ 0, 10, 0, 5 ]) |
Set axes manually |
title('title') xlabel('x-axis') ylabel('y-axis')
|
|
Axis labels and titles |
|
text(2,25,'hello') |
Insert text |
Log plots
MATLAB/Octave |
Python |
Description |
semilogy(a) |
semilogy(a) |
logarithmic y-axis |
semilogx(a) |
semilogx(a) |
logarithmic x-axis |
loglog(a) |
loglog(a) |
logarithmic x and y axes |
Filled plots and bar plots
MATLAB/Octave |
Python |
Description |
fill(t,s,'b', t,c,'g') % fill has a bug?
|
fill(t,s,'b', t,c,'g', alpha=0.2) |
Filled plot |
Functions
MATLAB/Octave |
Python |
Description |
f = inline('sin(x/3) - cos(x/5)') |
|
Defining functions |
ezplot(f,[0,40]) fplot('sin(x/3) - cos(x/5)',[0,40]) % no ezplot
|
x = arrayrange(0,40,.5) y = sin(x/3) - cos(x/5) plot(x,y, 'o')
|
Plot a function for given range |
Polar plots
MATLAB/Octave |
Python |
Description |
theta = 0:.001:2*pi; r = sin(2*theta);
|
theta = arange(0,2*pi,0.001) r = sin(2*theta)
|
|
polar(theta, rho) |
polar(theta, rho) |
|
Histogram plots
MATLAB/Octave |
Python |
Description |
hist(randn(1000,1)) |
|
|
hist(randn(1000,1), -4:4) |
|
|
plot(sort(a)) |
|
|
3d data
Contour and image plots
MATLAB/Octave |
Python |
Description |
contour(z) |
levels, colls = contour(Z, V, origin='lower', extent=(-3,3,-3,3)) clabel(colls, levels, inline=1, fmt='%1.1f', fontsize=10)
|
Contour plot |
contourf(z); colormap(gray) |
contourf(Z, V, cmap=cm.gray, origin='lower', extent=(-3,3,-3,3))
|
Filled contour plot |
image(z) colormap(gray)
|
im = imshow(Z, interpolation='bilinear', origin='lower', extent=(-3,3,-3,3))
|
Plot image data |
|
# imshow() and contour() as above |
Image with contours |
quiver() |
quiver() |
Direction field vectors |
Perspective plots of surfaces over the x-y plane
MATLAB/Octave |
Python |
Description |
n=-2:.1:2; [x,y] = meshgrid(n,n); z=x.*exp(-x.^2-y.^2);
|
n=arrayrange(-2,2,.1) [x,y] = meshgrid(n,n) z = x*power(math.e,-x**2-y**2)
|
|
mesh(z) |
|
Mesh plot |
surf(x,y,z) or surfl(x,y,z) % no surfl()
|
|
Surface plot |
Scatter (cloud) plots
MATLAB/Octave |
Python |
Description |
plot3(x,y,z,'k+') |
|
3d scatter plot |
Save plot to a graphics file
MATLAB/Octave |
Python |
Description |
plot(1:10) print -depsc2 foo.eps gset output "foo.eps" gset terminal postscript eps plot(1:10)
|
savefig('foo.eps') |
PostScript |
|
savefig('foo.pdf') |
PDF |
|
savefig('foo.svg') |
SVG (vector graphics for www) |
print -dpng foo.png |
savefig('foo.png') |
PNG (raster graphics) |
Data analysis
Set membership operators
MATLAB/Octave |
Python |
Description |
a = [ 1 2 2 5 2 ]; b = [ 2 3 4 ];
|
a = array([1,2,2,5,2]) b = array([2,3,4]) a = set([1,2,2,5,2]) b = set([2,3,4])
|
Create sets |
unique(a) |
unique1d(a) unique(a) set(a)
|
Set unique |
union(a,b) |
union1d(a,b) a.union(b)
|
Set union |
intersect(a,b) |
intersect1d(a) a.intersection(b)
|
Set intersection |
setdiff(a,b) |
setdiff1d(a,b) a.difference(b)
|
Set difference |
setxor(a,b) |
setxor1d(a,b) a.symmetric_difference(b)
|
Set exclusion |
ismember(2,a) |
2 in a setmember1d(2,a) contains(a,2)
|
True for set member |
Statistics
MATLAB/Octave |
Python |
Description |
mean(a) |
a.mean(axis=0) mean(a [,axis=0])
|
Average |
median(a) |
median(a) or median(a [,axis=0])
|
Median |
std(a) |
a.std(axis=0) or std(a [,axis=0])
|
Standard deviation |
var(a) |
a.var(axis=0) or var(a)
|
Variance |
corr(x,y) |
correlate(x,y) or corrcoef(x,y)
|
Correlation coefficient |
cov(x,y) |
cov(x,y) |
Covariance |
Interpolation and regression
MATLAB/Octave |
Python |
Description |
z = polyval(polyfit(x,y,1),x) plot(x,y,'o', x,z ,'-')
|
(a,b) = polyfit(x,y,1) plot(x,y,'o', x,a*x+b,'-')
|
Straight line fit |
a = x\y |
linalg.lstsq(x,y) |
Linear least squares $y = ax + b$ |
polyfit(x,y,3) |
polyfit(x,y,3) |
Polynomial fit |
Non-linear methods
Polynomials, root finding
MATLAB/Octave |
Python |
Description |
|
poly() |
Polynomial |
roots([1 -1 -1]) |
roots() |
Find zeros of polynomial |
f = inline('1/x - (x-1)') fzero(f,1)
|
|
Find a zero near $x = 1$ |
solve('1/x = x-1') |
|
Solve symbolic equations |
polyval([1 2 1 2],1:10) |
polyval(array([1,2,1,2]),arange(1,11)) |
Evaluate polynomial |
Differential equations
MATLAB/Octave |
Python |
Description |
diff(a) |
diff(x, n=1, axis=0) |
Discrete difference function and approximate derivative |
|
|
Solve differential equations |
Fourier analysis
MATLAB/Octave |
Python |
Description |
fft(a) |
fft(a) or
|
Fast fourier transform |
ifft(a) |
ifft(a) or
|
Inverse fourier transform |
|
convolve(x,y) |
Linear convolution |
Symbolic algebra; calculus
MATLAB/Octave |
Python |
Description |
factor() |
|
Factorization |
Programming
MATLAB/Octave |
Python |
Description |
.m |
.py |
Script file extension |
% % or #
|
# |
Comment symbol (rest of line) |
% must be in MATLABPATH % must be in LOADPATH
|
from pylab import * |
Import library functions |
string='a=234'; eval(string)
|
string="a=234" eval(string)
|
Eval |
Loops
MATLAB/Octave |
Python |
Description |
for i=1:5; disp(i); end |
for i in range(1,6): print(i) |
for-statement |
for i=1:5 disp(i) disp(i*2) end
|
for i in range(1,6): print(i) print(i*2)
|
Multiline for statements |
Conditionals
MATLAB/Octave |
Python |
Description |
if 1>0 a=100; end |
if 1>0: a=100 |
if-statement |
if 1>0 a=100; else a=0; end |
|
if-else-statement |
Debugging
MATLAB/Octave |
Python |
Description |
ans |
|
Most recent evaluated expression |
whos or who
|
|
List variables loaded into memory |
clear x or clear [all]
|
|
Clear variable $x$ from memory |
disp(a) |
print a |
Print |
Working directory and OS
MATLAB/Octave |
Python |
Description |
dir or ls
|
os.listdir(".") |
List files in directory |
what |
grep.grep("*.py") |
List script files in directory |
pwd |
os.getcwd() |
Displays the current working directory |
cd foo |
os.chdir('foo') |
Change working directory |
!notepad system("notepad")
|
os.system('notepad') os.popen('notepad')
|
Invoke a System Command |
|
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