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.rm #[ #] #H #V #F C
.IX Title "length Cg"
.TH length Cg "" "Cg Toolkit 2.2" "Cg Standard Library"
.UC
.SH "NAME"
\&\fBlength\fR \- return scalar Euclidean length of a vector
.SH "SYNOPSIS"
.IX Header "SYNOPSIS"
.Vb 5
\&  float length(float v);
\&  float length(float1 v);
\&  float length(float2 v);
\&  float length(float3 v);
\&  float length(float4 v);
.Ve
.Vb 5
\&  half length(half v);
\&  half length(half1 v);
\&  half length(half2 v);
\&  half length(half3 v);
\&  half length(half4 v);
.Ve
.Vb 5
\&  fixed length(fixed v);
\&  fixed length(fixed1 v);
\&  fixed length(fixed2 v);
\&  fixed length(fixed3 v);
\&  fixed length(fixed4 v);
.Ve
.SH "PARAMETERS"
.IX Header "PARAMETERS"
.Ip "v" 8
.IX Item "v"
Vector of which to determine the length.
.SH "DESCRIPTION"
.IX Header "DESCRIPTION"
Returns the Euclidean length of a vector.
.SH "REFERENCE IMPLEMENTATION"
.IX Header "REFERENCE IMPLEMENTATION"
\&\fBlength\fR for a \fBfloat3\fR vector could be implemented like this.
.PP
.Vb 4
\&  float length(float3 v)
\&  {
\&    return sqrt(dot(v,v));
\&  }
.Ve
.SH "PROFILE SUPPORT"
.IX Header "PROFILE SUPPORT"
\&\fBlength\fR is supported in all profiles.
.PP
Support in the fp20 is limited.
.SH "SEE ALSO"
.IX Header "SEE ALSO"
max, normalize, sqrt, dot
