# Python | Numpy np.legadd() method

Last Updated : 31 Dec, 2019

`np.legadd()` method is used to add one Legendre series to another.It returns the sum of two Legendre series `c1 + c2. `

Syntax : `np.legadd(c1, c2)`
Parameters:
c1, c2 :[ array_like ] 1-D arrays of Legendre series coefficients ordered from low to high.

Return : [ndarray] Array representing the Legendre series of their sum.

Code #1 :

 `# Python program explaining ` `# numpy.legadd() method  ` `   `  `# importing numpy as np   ` `# and numpy.polynomial.legendre module as geek  ` `import` `numpy as np  ` `import` `numpy.polynomial.legendre as geek ` `   `  `# Legendre series coefficients ` `s1 ``=` `(``1``, ``3``, ``5``)  ` `s2 ``=` `(``2``, ``4``, ``6``)     ` `   `  `# using np.legadd() method  ` `res ``=` `geek.legadd(s1, s2)  ` ` `  `# Resulting legendre series ` `print` `(res)  `

Output:

```[  3.   7.  11.]
```

Code #2 :

 `# Python program explaining ` `# numpy.legadd() method  ` `   `  `# importing numpy as np   ` `# and numpy.polynomial.legendre module as geek  ` `import` `numpy as np  ` `import` `numpy.polynomial.legendre as geek ` `   `  `# Legendre series coefficients ` `s1 ``=` `(``10``, ``20``, ``30``, ``40``, ``50``)  ` `s2 ``=` `(``2``, ``4``, ``6``, ``8``, ``10``)     ` `   `  `# using np.legadd() method  ` `res ``=` `geek.legadd(s1, s2)  ` ` `  `# Resulting legendre series ` `print` `(res)  `

Output:

```[ 12.  24.  36.  48.  60.]
```