How to Use Formulas in Autodesk Revit

Step-by-Step Guide

1. 1

   Step 1: Learn how to write a formula for exponentiation: use X raised to the power of Y = X ^ Y;

   It is an irrational number, but if we truncate it to 20 decimals it would be
   2.7182818284590452353.
   
   Revit usage = exp(x) ,, Fixed value = sqrt(999) Parameter = sqrt(Width) Formula= sqrt(Width + Height) , The logarithm of a number to a given base is the exponent to which the base must be raised in order to produce that number.
   
   For example, the logarithm of 1000 to base 10 is 3, because three factors of 10 must be multiplied to yield a thousand: 10 × 10 × 10 equals 1000 Revit usage = log(1000) , Force checked = 1 < 2 Force unchecked = 1 > 2 , Conditional statement uses this structure:
   IF (<condition>
   
   <result-if-true>
   
   <result-if-false>) Supported Conditional Operators < Less than > Greater than = Equal / Divide AND Both statements are true OR One of the statements is true NOT Statement is false Conditional statements can contain numeric values, numeric parameter names, and Yes/No parameters.
   
   Currently, <= and >= are not implemented.
   
   To express such a comparison, you can use a logical NOT.
   
   For example, a<=b can be entered as NOT(a>b) Simple IF Statement IF (Length < 900, <true>
   
   <false>) Formula That Returns Strings IF (Length < 900, “Opening too narrow”, “Opening OK”) Using logical AND IF ( AND (x = 1 , y = 2), <true>
   
   <false>) Returns <true> if both x=1 and y=2, else <false> Using logical OR IF ( OR ( x = 1 , y = 2 ) , <true>
   
   <false>) Returns <true> if either x=1 or y=2, else <false> Nested IF statements IF ( Length < 500 , 100 , IF ( Length < 750 , 200 , IF ( Length < 1000 , 300 , 400 ) ) ) Returns 100 if Length<500, 200 if Length<750, 300 if Length<1000 and 400 if Length>1000 IF with Yes/No condition Length > 40 Returns checked box (<true>) if Length > 40 NOT with Yes/No condition not(Viz) Returns checked box (<true>) if Yes/No parameter "Viz" is unchecked, and returns unchecked box (<false>) if Yes/No parameter "Viz" is checked.
   
   IF AND OR Returning the greatest of three values Say you have these 3 length parameters, and want a fourth parameter to return the greatest value/length of the 3:
   Length A Length B Length C Return Length (Returns the greatest of the three length parameters) Return Length = if(and(or(Length A > Length B, Length A = Length B), or(Length A > Length C, Length A = Length C)), Length A, if(and(or(Length B > Length A, Length B = Length A), or(Length B > Length C, Length B = Length C)), Length B, if(and(or(Length C > Length A, Length C = Length A), or(Length C > Length B, Length C = Length B)), Length C, 0 mm))) Another option is to use an extra "Calc" parameter, which is a bit more clumsy but also way easier and more manageable for us mortals.
   
   Calc = if(Length A > Length B, Length A, Length B) Return Length = if(Calc > Length C, Calc, Length C) , Known: a+b c = sqrt(a ^ 2 + b ^ 2) A = atan(a / b) B = atan(b / a) Known: a+c b = sqrt(c ^ 2
   - a ^ 2) A = asin(a / c) B = acos(a / c) Known: b+c a = sqrt(c ^ 2
   - b ^ 2) A = acos(b / c) B = asin(b / c) Known: c + A a = c * sin(A) b = c * cos(A) B = 90°
   - A Known: c + B a = c * cos(B) b = c * sin(B) A = 90°
   - B Known: a + B b = a * tan(B) c = a / cos(B) A = 90°
   - B Known: b + A a = b * tan(A) c = b / cos(A) B = 90°
   - A Known: a + A b = a / tan(A) c = a / sin(A) B = 90°
   - A Known: b + B a = b / tan(B) c = b / sin(B) A = 90°
   - B
2. 2

   Step 2: Learn how to write a formula for E raised to an x power E is a mathematical constant that is approximately equal to 2.7.

3. 3

   Step 3: Learn how to find the circumference and area of a circle with a formula in the program: Usage in Revit = pi() Circumference = pi() * (Radius * 2) Circumference = pi() * Diameter Circle Area = pi() * Radius ^ 2

4. 4

   Step 4: Learn how to find Square Roots of any number in this program.

5. 5

   Step 5: Learn how to solve logarithm problems.

6. 6

   Step 6: Learn how to force yes/no parameters to be checked or unchecked.

7. 7

   Step 7: Learn how to solve conditional statements.

8. 8

   Step 8: Learn how to solve a trigonometry problem in the software.

Detailed Guide

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