################### INFOS ###################
#                                           #
# Author : EepP                             #
#          eepp.b3ta.org                    #
#          eeppeliteloop@gmail.com          #
# Date : 12/12/05
# Applys to : TI-80 Calculators             #
# -----------------------------             #
# Program name : Tan Mker                   #
# Does : This program does create a tangent #
#    on a AX+BX+C parabola each given  #
#        X-coordinate value.                #
# Variables : A = Slope of parabola         #
#    B = Constant of X             #
#             C = Constant                  #
#             t = If is '1', turns on the   #
#                 looping for the tangent   #
#                 drawing, else ('0'),      #
#                 returns a single tangent  #
#                 at a given point.         #
#             i = If 't' is '0', 'i' is the #
#                 X-coordinate where you    #
#                 want the tangent to be    #
#                 drawn on the parabola,    #
#                 else ('t' = '1'), 'i' is  #
#                 the distance between each #
#                 point where the tangent   #
#                 will be drawn on the      #
#                 parabola, on all the      #
#                 domain.                   #
# Notes : The domain is like the ZSquare &  #
#    ZStandard together domain ; Xmin  #
#         is approx. -13 and Xmax is        #
#         approx. 13.                       #
#         The image is from -10 to 10, so   #
#         do not order a too big parabola   #
#         with your custom parameters.      #
#         The TI-80 processor isn't very    #
#         powerful, so be patient for the   #
#         tangents to be drawn.             #
#         Entering a value for 'i' of '1'   #
#         will draw so much tangent for the #
#         number of pixels the TI-80 can    #
#         handle that everything outside    #
#         the parabola will look filled of  #
#         points on.                        #
#         Entering a value of '0' for the   #
#         'A' parameter will give an error  #
#         because a parabola with a slope   #
#         value of '0' doesn't exists.      #
# Example : If you run the program and      #
#    enter the following values for  #
#           the variables ; [a = 0.2,       #
#           b = 0, c = -7, i = 3, t = 1] ;  #
#           the program is going to draw a  #
#           reversed parabola and then draw #
#           the tangents on the following   #
#           X-coordinate points of the      #
#           parabola : {-13, -10, -7, -4,   #
#           -1, 2, 5, 8, 11}. If you redo   #
#           this example but with a value   #
#           of '0' for 't', it will draw    #
#           the same parabola, but then     #
#           just one tangent at the         #
#           X-coordinate point '3' (value   #
#           of 'i').                        #
#                                           #
#############################################

##########
#>STARTS>#
##########

PROGRAM:TANMKER

:CLRDRAW:GRIDOFF
:CLRHOME
:-13.47826087->XMIN
:-XMIN->XMAX
:10->YMAX
:-YMAX->YMIN
:0->XSCL
:XSCL->YSCL
:
:1->A
:0->B
:0->C
:3->K
:
:DISP "TAN MKER"
:DISP "BY EEPP"
:DISP ""
:DISP "PRESS ANY KEY"
:DISP "TO CONTINUE..."
:PAUSE
:CLRHOME
:
:DISP "AX+BC+C"
:DISP ""
:INPUT "A=",A
:INPUT "B=",B
:INPUT "C=",C
:INPUT "I=",K
:INPUT "T=",T
:
:2(A)->D
:B->E
:0->F
:
:DRAWF (AX^2+BX+C)
:INT (XMIN)->N
:INT (XMAX)->O
:
:IF T=1:THEN
:FOR(I,N,O,K
:
:DRAWF ((DI+E)X+((AI^2+BI+C)-(DI+E)I))
:
:END
:ELSE
:
:DRAWF ((DK+E)X+((AK^2+BK+C)-(DK+E)K))
:END
:
:DISPGRAPH
:STOP

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#<END<# 
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