FourierCoefficient[expr,t,n]
gives the n coefficient in the Fourier series expansion of expr.
 coefficient in the Fourier series expansion of expr.
FourierCoefficient[expr,{t1,t2,…},{n1,n2,…}]
gives a multidimensional Fourier coefficient.
 
     
   FourierCoefficient
FourierCoefficient[expr,t,n]
gives the n coefficient in the Fourier series expansion of expr.
 coefficient in the Fourier series expansion of expr.
FourierCoefficient[expr,{t1,t2,…},{n1,n2,…}]
gives a multidimensional Fourier coefficient.
Details and Options
 
   - The   coefficient in the Fourier series expansion of coefficient in the Fourier series expansion of is by default given by is by default given by . .
- The  -dimensional Fourier coefficient is given by -dimensional Fourier coefficient is given by . .
- In the form FourierCoefficient[expr,t,n], n can be symbolic or an integer.
- The following options can be given:
- 
      
      Assumptions $Assumptions assumptions on parameters FourierParameters {1,1} parameters to define Fourier series GenerateConditions False whether to generate results that involve conditions on parameters 
- The function expr is assumed to be periodic in t with period  , except when otherwise specified by FourierParameters. , except when otherwise specified by FourierParameters.
- Common settings for FourierParameters include:
- 
      
      {1,1}   f(t) e-i n td t f(t) e-i n td tdefault settings {1,-2Pi}  f(t) ei 2π n td t f(t) ei 2π n td tperiod 1 {a,b}  general setting 
Examples
open all close allBasic Examples (2)
Scope (4)
Find the 3 Fourier coefficient for an exponential function:
 Fourier coefficient for an exponential function: 
General Fourier coefficient for a Gaussian function:
General Fourier coefficients for Abs:
Options (2)
FourierParameters (1)
Use a nondefault setting for FourierParameters:
Properties & Relations (4)
FourierCoefficient is defined by an integral:
Compute the exponential Fourier series using the individual coefficients:
FourierCoefficient is the same as InverseFourierSequenceTransform:
Related Guides
History
Text
Wolfram Research (2008), FourierCoefficient, Wolfram Language function, https://reference.wolfram.com/language/ref/FourierCoefficient.html.
CMS
Wolfram Language. 2008. "FourierCoefficient." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/FourierCoefficient.html.
APA
Wolfram Language. (2008). FourierCoefficient. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/FourierCoefficient.html
BibTeX
@misc{reference.wolfram_2025_fouriercoefficient, author="Wolfram Research", title="{FourierCoefficient}", year="2008", howpublished="\url{https://reference.wolfram.com/language/ref/FourierCoefficient.html}", note=[Accessed: 30-October-2025]}
BibLaTeX
@online{reference.wolfram_2025_fouriercoefficient, organization={Wolfram Research}, title={FourierCoefficient}, year={2008}, url={https://reference.wolfram.com/language/ref/FourierCoefficient.html}, note=[Accessed: 30-October-2025]}
 Fourier coefficient:
 Fourier coefficient: