Question: briefing codes for implicit plot

hi. i write a program consists a for loop in which cycle 'i', x[i] and hz[i] is calculated.

now i want to plot hz[i] correspond to each x[i].

this code is working but how to brief them?

hhz := piecewise(x < X[1], hz[1], X[1] < x and x < X[2], hz[2], X[2] < x and x < X[3], hz[3], X[3] < x and x < X[4], hz[4], X[4] < x and x < X[5], hz[5], X[5] < x and x < X[6], hz[6], X[6] < x and x < X[7], hz[7], X[7] < x and x < X[8], hz[8], X[8] < x and x < X[9], hz[9], X[9] < x and x < X[10], hz[10], X[10] < x and x < X[11], hz[11], X[11] < x and x < X[12], hz[12], X[12] < x and x < X[13], hz[13], X[13] < x and x < X[14], hz[14], X[14] < x and x < X[15], hz[15], X[15] < x and x < X[16], hz[16], X[16] < x and x < X[17], hz[17], X[17] < x and x < X[18], hz[18], X[18] < x and x < X[19], hz[19], X[19] < x and x < X[20], hz[20])