The following TI-Nspire CAS libraries are licensed under the Gnu Public License v3.0.

The libraries are:

Differential Equation Series Library - functions for series solutions of first- and second-order differential equations

Differential Equation Special Functions Library - Bessel Functions, Legendre Functions, Gamma Function, Log-Gamma Function

Fast Fourier Transform Library - functions for Fast Fourier Transform and Inverse Fast Fourier Transform

Fourier Series Library - functions for Fourier, Fourier sine, Fourier cosine series

List Utility Library - utility functions for list manipulations

Simplex Method Library - implementation of the Simplex Method for Linear Programming

To use the libraries:

1. Download the library,

2. Save the library in the TI-Nspire **mylib** folder,

3. In the user interface, open the **Library** pane and select **Refresh Libraries**

Libraries

deserieslib, v1.01 - functions for series solutions of differential equations:

Function Name | Description |

de_series_op() | Computes the series solutions for a differential equation centered on an ordinary point. |

de_series_sp() | Computes the series solutions for a differential equation centered on a singular point. |

de_singular_pts() | Finds the singular points (if any) of a differential equation. |

de_indicial_eqn() | Calculates the indicial equation and its roots r1 and r2 of a differential equation and a
singular point. |

bessel1() | Generates a series for a Bessel function of first order, Jn(x), where n is an integer. |

help() | Displays detailed information about using the library and its functions. |

Downloads for deserieslib

- deserieslib.tns (TI-Nspire Library, modified 29 September 2018)
- Using the Differential Equation Series Library (pdf)

despecfunc, v1.10 - special functions for solving differential equations:

Function Name | Description |

besseljn() | Returns Jn(x), the value of the Bessel Function of the first kind of integer order n. |

besselyn() | Returns Yn(x), the value of the Bessel Function of the second kind of integer order n. |

besselvalues() | Returns a list containing values of either Jn(x) or Yn(x) and the first and second derivatives of the function. |

gamma() | Returns the value of the Gamma function. |

help() | Displays detailed information about using the library and its functions. |

legendrepn() | Returns an expression for Pn(x), the Legendre polynomial of order n. |

legendreqn() | Returns an expression for Qn(x), the Legendre function of the second kind of order n. |

lngamma() | Returns the value of the natural logarithm of the Gamma function. |

Downloads for the differential equations special functions library

- despecfunc.tns (TI-Nspire Library, modified 4 June 2020)
- Using the Differential Equations Special Functions Library (pdf)

fftlib, v1.00 - functions for Fast Fourier Transform and Inverse Fast Fourier Transform.

Function Name | Description |

fft() | Transform point y values using the Fast Fourier Transform. |

ifft() | Invert transformed point y values using the Inverse Fast Fourier Transform. |

displayclist() | Display a list of values formatted as (real,imaginery) pairs. |

padlist() | Zero-pad a list of point y values to conform to fft() length requirement. |

unpadlist() | Remove zero-padding from a list of values after executing ifft(). |

help() | Displays detailed information about using the library and its functions. |

Downloads for fftlib

Back to Contentsfourierlib, v1.00 - functions for generating fourier series, fourier cosine series, and fourier sine series.

Function Name | Description |

fourier() | calculate a fourier series to approximate a function over an interval. |

fouriercos() | calculate a fourier cosine series to approximate a function over an interval. |

fouriersin() | calculate a fourier sine series to approximate a function over an interval. |

fouriercoscoef() | return a specified fourier cosine series coefficient for a function. |

fouriersincoef() | return a specified fourier sine series coefficient for a function. |

help() | Displays detailed information about using the library and its functions. |

isevenfunc() | Returns true if a named function is an even function and false if not. |

isoddfunc() | Returns true if a named function is an odd function and false if not. |

Downloads for fourierlib

Back to Contentslistutils, v1.00 - utility functions for manipulating TI-Nspire lists:

Function Name | Description |

append() | Adds an element to the end of a list. |

insert() | Inserts an element into a list after an element at a specified position (index). |

qsort() | sorts a list in ascending order. |

remove() | removes an element at the specified position (index) from the list. |

reverse() | reverses the order of elements in a list. |

Downloads for listutils

Back to Contentssimplexlib, v1.00 - Implementation of the Simplex Method for TI-Nspire CAS:

Function Name | Description |

help() | Displays detailed information about using the library and its functions. |

maximize() | Find the values of the variables that maximize an objective function given a list of constraints. |

minimize() | Find the values of the variables that minimize an objective function given a list of constraints. |

evaluate() | Calculate the value of an objective function given a list of variables and values that optimize
the objective function. |

dual() | Find the dual objective function and dual constraints associated with a primal objective function
and its constraints. |

standardize() | Convert a list of constraints to standard form. |

Downloads for simplexlib

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