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TimesBy

Status: Stable

documented, exercised by the test suite and/or worked examples, with no known limitations recorded.

Description

TimesBy[x, dx] or x *= dx

multiplies x by dx and returns the new value of x. x *= dx is equivalent to x = x dx.

Notes TimesBy has attribute HoldFirst. The first argument x can be a symbol or a Part expression referring to an existing value; dx may be a number, a symbolic expression, or a list (combined element-wise via the Listable attribute of Times). If x has no assigned value, TimesBy::rvalue is emitted and the expression is left unevaluated.

Examples (2)

Every input below was run against the current Mathilda build and its output recorded.

Basic examples (2)

In[1]:= q = 5; q *= 3; q
Out[1]= 15

In[2]:= w = {1., 2., 3.}; w[[3]] /= 4.; w
Out[2]= {1.0, 2.0, 0.75}

Implementation notes

Attributes: HoldFirst, Protected.

References

See also: AddTo, SubtractFrom, DivideBy, HoldFirst, Part, Plus, Times, Increment