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fix template
Carandraug (talk | contribs) (fix template) |
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outargs = nthargout (1:3, @myfunc) | outargs = nthargout (1:3, @myfunc) | ||
</syntaxhighlight>}} | </syntaxhighlight>}} | ||
=== Create a text table with fprintf=== | |||
(a.k.a. A funny formatting trick with fprintf found by chance) | |||
Imagine that you want to create a text table with fprintf with 2 columns of 15 characters width and both right justified. How to do this thing? | |||
That's easy: | |||
If the variable Text is a cell array of strings (of length <15) with two columns and a certain number of rows, simply type for the kth row of Text | |||
{{Code||<syntaxhighlight lang="octave" style="font-size:13px"> | |||
fprintf('%15.15s | %15.15s\n', Text{k,1}, Text{k,2}); | |||
</syntaxhighlight>}} | |||
The syntax '%<n>.<m>s' allocates '<n>' places to write chars and display the '<m>' first characters of the string to display. | |||
Example: | |||
{{Code|Example create a text table with fprintf|<syntaxhighlight lang="octave" style="font-size:13px"> | |||
octave:1> Text={'Hello','World'}; | |||
octave:2> fprintf('%15.15s | %15.15s\n', Text{1,1}, Text{1,2}) | |||
Hello | World | |||
</syntaxhighlight>}} | |||
===Load comma separated values (*.csv) files=== | |||
{{Code|Load comma separated values files|<syntaxhighlight lang="octave" style="font-size:13px"> | |||
A=textread("file.csv", "%d", "delimiter", ","); | |||
B=textread("file.csv", "%s", "delimiter", ","); | |||
inds = isnan(A); | |||
B(!inds) = num2cell(A(!inds)) | |||
</syntaxhighlight>}} | |||
This gets you a 1 column cell array. You can reshape it to the original size by using the <code>reshape</code> function | |||
The next version of octave (3.6) implements the <code>CollectOutput</code> switch as seen in example 8 here: http://www.mathworks.com/help/techdoc/ref/textscan.html | |||
Another option is to use the function <code>csvread</code>, however this function can't handle non-numerical data. | |||
===Using variable strings in commands=== | |||
For example, to plot data using a string variable as a legend: | |||
Option 1 (simplest): | |||
{{Code|Using variable strings in commands. op1|<syntaxhighlight lang="octave" style="font-size:13px"> | |||
legend = "-1;My data;"; | |||
plot(x, y, legend); | |||
</syntaxhighlight>}} | |||
Option 2 (to insert variables): | |||
{{Code|Using variable strings in commands. op2|<syntaxhighlight lang="octave" style="font-size:13px"> | |||
plot(x, y, sprintf("-1;%s;", dataName)); | |||
</syntaxhighlight>}} | |||
Option 3 (not as neat): | |||
{{Code|Using variable strings in commands. op3|<syntaxhighlight lang="octave" style="font-size:13px"> | |||
legend = 'my legend'; | |||
plot_command = ['plot(x,y,\';',legend,';\')']; | |||
eval(plot_command); | |||
</syntaxhighlight>}} | |||
These same tricks are useful for reading and writing data files with unique names, etc. | |||
== Mathematics == | == Mathematics == | ||
=== Test if a number is a integer === | |||
There's several menthods to do this. The simplest method is probably {{Codeline|<nowiki>fix (x) == x</nowiki>}} | |||
=== Find if a number is even/odd === | === Find if a number is even/odd === | ||
==== Problem ==== | ==== Problem ==== | ||
| Line 191: | Line 254: | ||
get (0, "screensize") | get (0, "screensize") | ||
</syntaxhighlight>}} | </syntaxhighlight>}} | ||