Hey @Rich Howard,
I've been having some trouble with using temporary variables in the equation parser; whether I set them to a constant or to a calculated value, Assisi doesn't seem to recognize them. Can Assisi handle temporary variables, and if so, how do I set them?
As an example, here is settings snippet for a parsed tree shape equation.
' Hann, D.W. 2011. Revised volume and taper equations for six major conifer species in southwest Oregon. Department of Forest Engineering, Resources, and Management., Oregon State University, Corvallis, Oregon. Forest Biometrics Research Paper 2. 14p. ' Equations 7 & 10, Tables 6 & 10, Douglas-fir b1 = 0.92443655 b2 = 0.988866545 b3 = -0.0341455033 b11 = -0.550298007 b12 = -0.69479837 b13 = -0.0613100423 b21 = 0.356974513 RH = (H - 4.5) / (HT - 4.5) HD = (HT - 4.5) / DBH PDIB = (b1 * DBH ^ b2) * EXP(b3 * (1.0 - (HCB / HT)) ^ 0.5) WLT = (alpha * HCB - 4.5) / (HT - 4.5) I1 = IIF(RH > WLT, 1, 0) I2 = IIF(WLT > 0, 1, 0) JP1 = (RH - 1.0) / (WLT - 1.0) JP2 = (WLT - RH) / (WLT - 1.0) Z0 = 1.0 - RH + I2 * (RH + I1 * (JP1 * (1.0 + JP2) - 1.0)) - (RH - 1.0) * (RH - I2 * RH) Z1 = (I2 * (RH + I1 * (JP1 * (RH + (WLT * JP2)) - RH)) - (RH - 1.0) * (RH - I2 * RH)) Z2 = I2 * ((RH ^ 2) + I1 * ((JP1 * WLT * (2 * RH - WLT + (WLT * JP2)) - RH ^ 2)) DIB = PDIB * (Z0 + (b11 + b12 * HD + b13 * HD ^ 2) * Z1 + b21 * Z2)After an initial error that the term 'Value' was not included (I'm guessing this is the expected output value?), I received this error:
Failed to set up stand. Failed to set up Plot 99, Tree 1 (DF): Failed to create tree of shape PARSE. 'CFM-SIS FVS-CA' calibration, species 'Douglas-fir' Failed to parse equation: term 'Diameter' not found in: ' hann, d.w. 2011. revised volume and taper equations for six major conifer species in southwest oregon. department of forest engineering, resources, and management., oregon state university, corvallis, oregon. forest biometrics research paper 2. 14p. ' equations 7 & 10, tables 6 & 10, douglas-fir b1 = 0.92443655 b2 = 0.988866545 b3 = -0.0341455033 b11 = -0.550298007 b12 = -0.69479837 b13 = -0.0613100423 b21 = 0.356974513 rh = (h - 4.5) / (ht - 4.5) hd = (ht - 4.5) / dbh pdib = (b1 * dbh ^ b2) * exp(b3 * (1.0 - (hcb / ht)) ^ 0.5) wlt = (alpha * hcb - 4.5) / (ht - 4.5) i1 = iif(rh > wlt, 1, 0) i2 = iif(wlt > 0, 1, 0) jp1 = (rh - 1.0) / (wlt - 1.0) jp2 = (wlt - rh) / (wlt - 1.0) z0 = 1.0 - rh + i2 * (rh + i1 * (jp1 * (1.0 + jp2) - 1.0)) - (rh - 1.0) * (rh - i2 * rh) z1 = (i2 * (rh + i1 * (jp1 * (rh + (wlt * jp2)) - rh)) - (rh - 1.0) * (rh - i2 * rh)) z2 = i2 * ((rh ^ 2) + i1 * ((jp1 * wlt * (2 * rh - wlt + (wlt * jp2)) - rh ^ 2)) value = pdib * (z0 + (b11 + b12 * hd + b13 * hd ^ 2) * z1 + b21 * z2)I think this brings up a secondary issue: what are the expected values for each parse field? I've seen the same thing with bark equations. It would be helpful to have the expected final output value defined for each parse equation option, including units.