formatting - SetPrecision with indexed variables

I have an expression as below:

Equations = 2.0799361919940695` x[1] + 3.3534325557330327` x[1]^2 - 
   4.335179297091139` x[1] x[2] + 1.1989715511881491` x[2]^2 - 
   3.766597877399148` x[1] x[3] - 0.33254815073371535` x[2] x[3] + 
   1.9050048836042945` x[3]^2 + 1.1386715715291826` x[1] x[4] + 
   2.802846492104668` x[2] x[4] - 0.6210244597295915` x[3] x[4] + 

   4.943369095158792` x[4]^2

I want to write it in an output file. So I use the below code:

removebracketvar[x_] := 
  StringReplace[
   StringReplace[
    ToString[x], {"[" -> "", "]" -> "", "," -> "", "*^" -> "e", 
     ".*" -> ".0*"}], Whitespace -> ""];
SetDirectory["C:\\folder"];
WriteString["eqfile.txt", 

  removebracketvar[
   ToString[Equations , InputForm, NumberMarks -> False]] ];
Close["eqfile.txt"]

The slight problem with the code for me is that it inserts the floating point numbers up to 16 digits of precision. I just want them to around up to 10 digits of precision. When I use SetPrecision[Equations,10], it weirdly changes x[1] etc. to x[1.0000000], etc.! I want to leave the variables as they are but want to change the floating points to less number of digits after the decimal point. What would be the best way of doing this?

Comments

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I have several sigmoidal fits to 3 different datasets, with mean fit predictions plus the 95% confidence limits (not symmetrical around the mean) and the actual data. I would now like to show these different 2D plots projected in 3D as in but then using proper perspective. In the link here they give some solutions to combine the plots using isometric perspective, but I would like to use proper 3 point perspective. Any thoughts? Also any way to show the mean points per time point for each series plus or minus the standard error on the mean would be cool too, either using points+vertical bars, or using spheres plus tubes. Below are some test data and the fit function I am using. Note that I am working on a logit(proportion) scale and that the final vertical scale is Log10(percentage). (* some test data *) data = Table[Null, {i, 4}]; data[[1]] = {{1, -5.8}, {2, -5.4}, {3, -0.8}, {4, -0.2}, {5, 4.6}, {1, -6.4}, {2, -5.6}, {3, -0.7}, {4, 0.04}, {5, 1.0}, {1, -6.8}, {2, -4.7}, {3, -1....

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