Difference between revisions of "Array.foldl()"
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| Line 19: | Line 19: | ||
) | ) | ||
| − | 1 2 - | + | 0 1 -1 |
| + | |||
| + | -1 2 -3 | ||
| − | - | + | -3 3 -6 |
| − | - | + | -6 4 -10 |
| − | - | + | -10 5 -15 |
| − | - | + | -15 |
| Line 48: | Line 50: | ||
-13 | -13 | ||
| + | |||
| + | |||
| + | a=1..3; | ||
| + | a.foldr(MINUS,2) | ||
| + | |||
| + | -4 (2-1-2-3) | ||
==See Also== | ==See Also== | ||
| − | [[Array. | + | [[Array.fold()|fold ]] |
[[Array.foldr()|foldr ]] | [[Array.foldr()|foldr ]] | ||
Latest revision as of 04:58, 24 April 2020
Array.foldl(SomFunction, SomeStartValue)
At each element, SomeFunction (that can take two parameter values) are called in sequence for element from the left. The second parameter is the last value of evaluation of the given SomeFunction. For the very first element, the SomeStartValue is passed as the second parameter, if present. If no SomeStartValue is provided, it starts with the first two as the pair to start with.
a=1..5;
a.foldl(
function (last,x)
{
OUTPUT([last,x,(last-x)]);
return(last-x)
},
0
)
0 1 -1
-1 2 -3
-3 3 -6
-6 4 -10
-10 5 -15
-15
a=1..5;
a.foldl(
function (last,x)
{
OUTPUT([last,x,(last-x)]);
return(last-x)
}
)
1 2 -1
-1 3 -4
-4 4 -8
-8 5 -13
-13
a=1..3;
a.foldr(MINUS,2)
-4 (2-1-2-3)