# Using the listed results for a following calculations

GROUPS:
 Hello, I have an equation and it is generetion a list of x values for a given Q. I would like to use those x values for a following calculation such as I would like to muliply them with some constant values. Can you guide me how to do that? Also I am would like to Plot the results Q versus x after calculation. If you know a simpler way of solveing the equation I would like to hear that as well. Here is the equationThank you in advance. Table[Grid[Table[FindRoot[     1.4712199999999998 Log[         0.3080613378622851 + 1.4517158853306498 y*Q/x] +       5.52759 Log[         3.2461067881456693 +          1.4517158853306498 y*Q/x] - (1.4712199999999998 Log[           0.3080613378622851 + 1.4517158853306498 0] +         5.52759 Log[3.2461067881456693 + 1.4517158853306498 0])      == (3.88212 Log[         1. + 0.04908626625087394 (1 - y)*           Q/(1 - x)]) - (3.88212 Log[1. + 0.04908626625087394 0]),    {x, .999}], {Q, 0.05, 1, 0.05}]], {y, {0.15}}]
Answer
4 years ago
1 Reply
 Bill Simpson 1 Vote Using Grid you are "desktop publishing" your result which makes it nice to look at and pretty close to impossible to use for further calculations. Try this instead. In[1]:= allx = Table[Table[x/.FindRoot[1.4712199999999998 Log[0.3080613378622851 + 1.4517158853306498 y*Q/x]+       5.52759 Log[3.2461067881456693 + 1.4517158853306498 y*Q/x] - (1.4712199999999998 Log[       0.3080613378622851 + 1.4517158853306498 0] + 5.52759 Log[3.2461067881456693 +        1.4517158853306498 0]) == (3.88212 Log[1. + 0.04908626625087394 (1 - y)*Q/(1 - x)]) - (3.88212 Log[       1. + 0.04908626625087394 0]), {x, .999}], {Q, 0.05, 1, 0.05}], {y, {0.15}}]  Out[1]= { {0.89657, 0.896151, 0.895753, 0.895373, 0.895011, 0.894666, 0.894337, 0.894024, 0.893725, 0.893439,  0.893167, 0.892907, 0.892659, 0.892422, 0.892197, 0.891981, 0.891776, 0.89158, 0.891393, 0.891214}}That isn't as pretty to look at but now all your results are in the list allx and you can subscript them to extract single values, multiply allx by 3 to multiply all of them by 3, etc.Notice that little x/. inserted in front of the FindRoot. That is substituting how FindRoot returns information about a root with just the value of the root it finds.
Answer
4 years ago