Changes in version 2026-01-27                      

  - fixed a unit test due to new version of nlsic

v2.5 2025-05-16

  - least norm is replaced by minimizing the norm of n-th derivative
    coeffs in under-determined systems
  - dmat() gains a new parameter nderiv
  - fixed flate tv curve in iknots()

v2.4 2025-03-12

  - added abcisse range check for arguments in equality constraints of
    smbsp()
  - iknots: tv can be smoothed for xki finding
  - iknots: tv is smoothed till at least one x point belongs to each
    knot interval
  - iknots: if lenfit is 0, all tv values are used for linear
    interpolation
  - smbsp: outside or border xki are now removed with warning, not error
  - [fit]smbsp: added regular_grid parameter
  - fitsmbsp: default precision in xki fit is 0.01dx instead of 0.1dx
  - fitsmbsp: minimal distance imposed between knots is now dx, not
    dx/10
  - par2bsp: if select parameter is NULL, it is considered as missing

v2.3.0 2025-02-05

  - added imat(), integration matrix computation
  - fixed dmat() for nqw
  - fixed extra quotes in bspline manual
  - added parameter 'lenfit' to iknots()

v2.2.2 2024-07-02

  - fixed typo in example of pbsc()
  - fixed syntax error in manual for bsc() and bsp()
  - fixed missing variable in test of example for pbsc()
  - fixed missing export for pbsc()

v2.2.1 2023-05-30

  - fixed typo in rgl example of bcurve()
  - fixed NEWS mention of parr() for v2.2.
  - added pbsc()

v2.2 2023-05-26

  - added bcurve() for building nD curves from a set of control points
  - added parr() polynomial formulation of B-splines

v2.1 2022-09-26

  - smbsp() can estimate covariance matrix of estimated coefficients
  - added dmat() for differentiation operator
  - ipk() is now exported and tested
  - fixed 0-value for abscissas on the right hand side of the knot
    interval

v2.0.1 2022-04-19

  - bsc() can calculate Jacobian of basis vectors as function of knots.
    By consequence, the suggestion of numDeriv package is removed
  - added jacw() calculating Jacobian of B-spline with weights
  - added ibsp() for integration
  - now, iknots() can deal with repeated x values
  - added monotonicity and positivity optional constraints
  - added Copyright field to DESCRIPTION
  - fixed inequality generation in fitsmbsp()
  - fixed gcc-12 compile error

v1.0.2 2022-03-17

  - fixed ipk() ASAN problem signaled by R CRAN team
  - fixed export of par2bsp()
  - fixed error in example of fitsmbsp()
  - fixed debug printing in iknots()
  - increased resolution from 5 to 10 intervals for tv fitting by linear
    B-splines in iknots()
  - forced monotonicity in iknots() despite possible round-off errors
  - added URL and BugRepport in DESCRIPTION

v1.0.1 2022-03-11

  - First release on CRAN