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THIS IS DOCUMENTATION FOR AN OBSOLETE PRODUCT.
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LengthWhile
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BUILT-IN MATHEMATICA SYMBOL
Applying Functions Repeatedly
Tutorials »
|
Length
Position
TakeWhile
See Also »
|
Elements of Lists
Functional Iteration
Functional Programming
Summary of New Features in 7.0
New in 6.0: List Manipulation
More About »
LengthWhile
LengthWhile
gives the number of continuous elements
starting at the beginning of
list
for which
is
True
.
MORE INFORMATION
LengthWhile
can be used on an object with any head, not necessarily
List
.
EXAMPLES
CLOSE ALL
Basic Examples
(1)
Find the length of the run of elements below 10:
Find the length of the run of elements below 10:
In[1]:=
Out[1]=
Scope
(1)
Elements of the list can be any expression:
Generalizations & Extensions
(1)
Use on an expression with head
f
:
The result is the same as for a list of the values:
Applications
(1)
Find the length of the run of digits in
before a 7 occurs:
Properties & Relations
(3)
LengthWhile
gives the length of the result from
TakeWhile
:
LengthWhile
is equal to
Length
if
is
True
for all elements:
Otherwise it is 1 less than the first position for which
is not
True
:
Possible Issues
(1)
The count terminates for any value of
that is not
True
:
SEE ALSO
Length
Position
TakeWhile
TUTORIALS
Applying Functions Repeatedly
MORE ABOUT
Elements of Lists
Functional Iteration
Functional Programming
Summary of New Features in 7.0
New in 6.0: List Manipulation
New in 6 | Last modified in 7
starting at the beginning of list for which 
is True.
before a 7 occurs:
is not True:
that is not True:
EXAMPLES
Basic Examples 
Scope 
