DETERMINATION OF WAVE FORM 655 



The calculations may be systematized by *the use of properly 

 prepared forms such, for example, as that following. 



The numerical work may be checked by using particular values 

 of*. 



2/o = (Bi + Bn) + (B t + B 9 ) + (B 6 + B 7 ) 

 2/6 = (Ai - An) - (A 8 - A 9 ) + (A 5 - A 7 ) 

 7/3 + 2/9 = 2 sin 45 [(Ai + AH) + (A 3 + A 9 ) - (A B + A 7 )] 

 2/3-2/9 = 2 sin 45 [(Bi - ) - (B s - B 9 ) - (B b - B^ 

 2/4 + 2/8 = 2 sin 60 [(Ai - An) - (A 5 - A 7 )] 



Following the plan outlined above, schedules corresponding to 

 any number of measured ordinates may be prepared. If even 

 harmonics be present it is necessary to divide the whole wave 

 into 2n parts. 



The values of the. coefficients A and B, obtained as above by the 

 use of a definite number of measured ordinates, determine a 

 curve which coincides with the original curve at the measured 

 points and diverges from the original curve at intermediate points; 

 consequently the more complicated the wave form, the greater 

 the number of ordinates which must be used. A schedule based 

 on 18 instead of 12 ordinates is frequently necessary. As a check 

 on the sufficiency of the analysis, values of y intermediate 

 between the measured values should be calculated and compared 

 with the actual ordinates at the same points. 



