Scilab Bag Of Tricks - Claymore

(1.) / ([1 2 3])
Chapter 2. Pitfalls
where the parentheses have been introduced for clarity. This behavior is described in SCI/README,
and in the Scilab FAQ .
We suggest to avoid whitespace that influences the calculation by not letting the decimal point stick
out on either side. That way expressions with numerals will always be interpreted correctly. For our
example this means
->1.0./ [1 2 3]
ans =
! 1. 0.5 0.3333333 !
which gives what we had in mind.
2.2. Vector Construction
The square bracket operator [ ] is a convenient means to construct vectors. There even exists an
idiom to build a matrix with brackets, which is shown in Example 2-1.
Example 2-1. Building a matrix column-by-column and row-by-row
mat = []
for i = 1:n
row = []
for j = 1:m
... – compute matrix entry
expr = ...
row = [row expr]
end
mat = [mat; row]
end
Rows are separated by semi-colons or newlines, which actually is straight forward. Columns are
separated by commas, or spaces—and here comes trouble. First, comma and space serve the same
purpose, and are interchangeable. Thus, the following expressions have the same result.
[1 2 3 4]
[1,2,3,4]
[1 2 3,4]
[ 1, 2 3 , 4 ]
Second, a space is sometimes considered a column-separating space, sometimes a intra-expression
space. This can lead to some confusion as the following three matrix definitions demonstrate. Who
gets all of them right without peeking at the answers?
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