#
#
# Written by:
# -- 
# John L. Weatherwax                2009-04-21
# 
# email: wax@alum.mit.edu
# 
# Please send comments and especially bug reports to the
# above email address.
#
# EPage 
# 
#-----

#postscript("../../WriteUp/Graphics/Chapter7/section_2_prob_4.eps", onefile=FALSE, horizontal=FALSE)

x_1 = seq( -100, +600, length=100 )
x_2 = 350 - x_1
plot( x_1, x_2, type='l' )

x_2 = 500 - x_1
lines( x_1, x_2, type='l' )

abline( v=0 )
abline( h=0 ) 

polygon( c(200,250,400,200), c(150,100,100,300), col="gray" ) 

grid()

#dev.off()


#postscript("../../WriteUp/Graphics/Chapter7/section_2_prob_5.eps", onefile=FALSE, horizontal=FALSE)

x_1 = seq( -5, +35, length=100 )
x_2 = 30 - x_1 
plot( x_1, x_2, type='l' )

abline( v=3 )
abline( v=15 )
abline( h=22 )

abline( h=0 )

polygon( c(3,15,15,8,3), c(0,0,15,22,22), col="gray" ) 

grid()

#dev.off()


#postscript("../../WriteUp/Graphics/Chapter7/section_2_prob_10.eps", onefile=FALSE, horizontal=FALSE)

x = seq( -1, 6, length=100 )
y = ( 1 - 0.9 * x ) / 0.6
plot( x, y, type='l', ylim=c(-0.5,4) )

y = ( 0.4 - 0.1 * x ) / 0.4
lines( x, y, type='l' )

abline( v=0 )
abline( h=0 )

y_middle = 2.6/3
x_middle = ( 0.4 - 0.4 * y_middle ) / 0.1 
polygon( c(0,0,x_middle,4,7,7), c(5,5/3,y_middle,0,0,5), col='gray' ) 

grid()

#dev.off()


# Some simple calculations:
# 
x_eps = c(0,0.5333333,4)
y_eps = c(1.666667,0.8666667,0)
for( ii in 1:3 ){
  #print( x_eps[ii] + 0.5 * y_eps[ii] ) # cost for part (c)
  #print( 0.75 * x_eps[ii] + 0.5 * y_eps[ii] ) # cost for part (d)
  print( x_eps[ii] + y_eps[ii] ) # cost for part (e)
}


#postscript("../../WriteUp/Graphics/Chapter7/section_2_prob_14.eps", onefile=FALSE, horizontal=FALSE)

x = seq( -1, 6, length=100 )
y = ( 0.6 - 0.9 * x ) / 0.6
plot( x, y, type='l', ylim=c(-0.5,4) )

y = ( 0.4 - 0.1 * x ) / 0.4
lines( x, y, type='l' )

abline( v=0 )
abline( h=0 )

polygon( c(0,0,4,7,7), c(5,1,0,0,5), col='gray' ) 

grid()

#dev.off()