Photon Help
Click this link to ask a question specifically about Photon.

Graphing Functions
 To graph a function, simply type it in the text box and click "Go" or hit the ENTER key. It's that easy. Both explicit and implicit functions are supported, for both rectangular and polar coordinates. Below are examples of valid entries Photon will recognize:
Explicit for y: Explicit for x: Explicit for polar radius: Explicit for polar theta: Implicit rectangular: Implicit polar: Parametric rectangular: Parametric polar: Parametric 3D: 3D surface: Parametric 3D surface: Differential slope field: Sequential: Summation: 2D Vector Field: 3D Vector Field: Line integral of vector field: First Derivative: Second Derivative: Numeric Integration: Defined limits (applicable to nearly all types): 
y = x^2 + 1 x = 2*y r = sin(3*th) th = 2*r x^2  y^2 = 1 th^2 * r^2 = 1 x = t^2; y = t/2 r = sin(t)*3 + 1; θ = 2*t x = cos(t); y = sin(t); z = t/5; 20; 20 z = sin(x*y) x = (2 + cos(u))*cos(2*v); y = (2 + cos(u))*sin(2*v); z = sin(u) + v y' = sin(x*y) a_n = (1)^n 2*k; 0; 4 sin(y)*i + sin(x)*j sin(x*y)*i + j  x*k (any function on top of a 2D or 3D vector field) d y = x^2 dd y = x^2 i y = x^2; 1.5; 1 y = x^2 + 1; 1; 1 
 To make things less cumbersome, Photon will automatically insert symbols as you type. For example, typing the keys "x" and then "2" and then hitting ENTER will cause Photon to interpret that as "y = x^2", and typing "2" and then "x" will be interpreted as "y = 2*x". If you want to block one of your functions from being graphed, just place a single quotation ( ' ) in front of your text entry. That way, you'll still have it on hand if you need it.
Plotting and Fitting Data
 To start plotting data, click on the third icon (the one with the data points and a line through them). You can enter your x and y data and choose to fit a plot to it. Single variable statistics for both x and y, such as the five number summary, will appear on the righthand side of the window.
Creating Variables
 Any variable you create must be one letter long. To create a variable, you must use the " := " sign. For example, type "x", then type " : ", then type "2". Notice that the equals sign was inserted as soon as you typed a colon. Press ENTER or click "Go", and your variable will be created. You can use that variable in your calculations. Note: you cannot create variables named "e" since e is the constant for the base of the natural logarithm.
 You can also create functions this way, as long as the name of the function is one letter long. Try typing "f(x) := x/2" and hit ENTER. Then type "f(4)" and hit enter. The answer "2" will be displayed, because 4 / 2 is equal to 2.
Using Matrices
 To create a matrix and do matrix operations, click on the fourth button in the upper right corner  the one with a small matrix pictured. If Photon has fraction mode turned on, solutions will be expressed as fractions.
Unit Conversion
Photon supports unit conversions as well. To convert units, click on the fifth button in the upper right corner of the window. Type your number as well as your unit into the text box, and a list of available units will be calculated below. Here are the supported units Photon will recognize (units with numbers by them indicate "squared" or "cubed"):
Acceleration:  m/s2  ft/s2  mi/hr/s  g's Angles:  revolutions  radians  degrees  gradians  arcminutes  arcseconds Area:  m2  km2  in2  ft2  yd2  mi2  hectares  acres Density:  kg/l  kg/m3  g/cm3  oz/m3  lb/ft3 Energy:  J  kJ  calories  Calories  Wh  kWh  ev  BTU  therm  ftlb Fuel Consumption:  km/l  mpg Length:  m  km  cm  mm  micrometer  nm  mi  yd  ft  in  nauticalmile  AU  ly  pc Mass / Force: (mass and force are combined for convenience, assuming Earth gravity)  N  lb  dyne  kg  oz  g  mg  microgram  ton Molar Mass: (Examples: "1 mol KSO4" "2 g CoCl2" "3.0E23 part Ba(BrF4)2")  g  mol  part 
Power:  W  cal/s  Cal/s  BTU/min  hp Prefixes:  yotta  zetta  exa  peta  tera  giga  mega  kilo  hecto  deca  u  deci  centi  milli  micro  nano  pico  femto  atto  zepto  yocto Pressure:  Pa  atm  bar  psi  mmHg  torr Speed:  m/s  cm/s  mph  km/h  ft/s  c  knot Time:  ns  microsecond  ms  s  min  hr  day  week  month  year  decade  century  millennium Volume:  m3  gal  qt  pt  cup  floz  T  tsp  l (liter)  ml  ft3  in3 
Speech Recognition
Speech recognition can be activated by clicking the small microphone icon in the text entry box or by pressing ALT + SPACE on the keyboard. Whenever the text box is green, your microphone will listen for your voice. If the text box is white, speech recognition is not active. Speech recognition can be turned off by saying "deactivate," by pressing ALT + SPACE, or by clicking the microphone icon again.
Options for speech recognition can be found in the options window (Tools > Options), on the "Speech" tab.
Here are some important things to remember:
 Use the word "let" to create a variable. Example: say "let a equal 2."
 Use the word "quantity" or "open" to add a "(" character, and use the word "close" to add a ")" character.
 If automatic calculation is turned off, you can pause for a moment and then continue speaking to close off parentheses. Example: say "sine of x <pause> plus one." Then say "go."
 Say "all" to wrap parentheses around an entire phrase. Example: say "x plus one all over two."
 Say "cancel" to delete the contents of the text box.
 Say "clear" to delete your history.
 Say "enable fraction mode" or "disable fraction mode" to switch fraction mode.
 Say "degree mode" or "radian mode" to switch modes.
Finally, you can edit your entries in the history section by clicking the area where the text is, moving the mouse to the area you need to correct, and speaking the phrase again. This is useful if your computer misinterprets what you say.
Function Library
Below is a list of all the math functions available to you, with an example for each function. Functions are not case sensitive, so don't worry about typing capital letters. The functions in this list are ordered in the same way that they are ordered in Photon, underneath Tools > Insert Function. Also, the examples below assume that the calculator is in radian mode with fractions turned off.
Function name
Trigonometric Functions: Radians to Degrees Degrees to Radians Sine Cosine Tangent Cosecant Secant Cotangent Hyperbolic Sine Hyperbolic Cosine Hyperbolic Tangent Hyperbolic Cosecant Hyperbolic Secant Hyperbolic Cotangent Inverse Trigonometric Functions: Inverse Sine Inverse Cosine Inverse Tangent Inverse Tangent XY Inverse Cosecant Inverse Secant Inverse Cotangent Inverse Hyperbolic Sine Inverse Hyperbolic Cosine Inverse Hyperbolic Tangent Inverse Hyperbolic Cosecant Inverse Hyperbolic Secant Inverse Hyperbolic Cotangent General Arithmetic: Absolute Value Square Root e ^ x Natural Log Log Base Ten Log Base b Modulus Fractional Part Random Decimal Sign Integer Arithmetic: Greatest Common Factor Lowest Common Multiple Convert to Base 2 Convert to Base 8 Convert to Base 16 Round Integer Part Fix Nth Prime Nth Fibonacci Factorial Permutations Combinations Complex Numbers: Add Subtract Multiply Divide Square Root Stat. Distributions: Binomial PDF Binomial CDF Chi square PDF Chi square CDF F PDF F CDF Geometric PDF Geometric CDF Inverse Normal Normal PDF Normal CDF Poisson PDF Poisson CDF Student t PDF Student t CDF Vectors: Dot Product Cross Product Convert to Magnitude  Angle Form Convert to 3D Magnitude  Angle Form Convert to Vector Component Form Convert to 3D Vector Component Form 
Definition
Converts a radian measure into degrees. Converts a degree measure into radians. Calculates the sine of an angle. Calculates the cosine of an angle. Calculates the tangent of an angle. Calculates the cosecant of an angle. Calculates the seceant of an angle. Calculates the cotangent of an angle. Calculates the sine of a hyperbolic angle. Calculates the cosine of a hyperbolic angle. Calculates the tangent of a hyperbolic angle. Calculates the cosecant of a hyperbolic angle. Calculates the secant of a hyperbolic angle. Calculates the cotangent of a hyperbolic angle. Calculates the angle of a sine ratio. Calculates the angle of a cosine ratio. Calculates the angle of a tangent ratio. Calculates the angle of a tangent ratio given by the point (x, y). Calculates the angle of a cosecant ratio. Calculates the angle of a secant ratio Calculates the angle of a cotangent ratio. Calculates the hyperbolic angle of a sine ratio. Calculates the hyperbolic angle of a cosine ratio. Calculates the hyperbolic angle of a tangent ratio. Calculates the hyperbolic angle of a cosecant ratio. Calculates the hyperbolic angle of a secant ratio. Calculates the hyperbolic angle of a cotangent ratio. Determines a number's distance from zero. Calculates the square root of a number. Raises the base of the natural logarithm to the power of x. Calculates the natural logarithm of x. Calculates the logarithm of x, with a base of 10. Calculates the logarithm of x, with a base of b. Determines the remainder of the division of two numbers. Returns the "decimal" portion of a number. Computes a random number between 0 and 1. Determines the sign of a number. GCF of two numbers. LCM of two numbers. Converts an integer to base 2. Converts an integer to base 8. Converts an integer to base 16. Rounds a number to the nearest integer. Returns the highest integer less than x. Returns the nearest integer going towards zero from x. Calculates the nth prime. Calculates the nth term in the Fibonacci Sequence. Calculates the multiplicative factorial of a number. Computes the number of permutations in a set of objects. Computes the number of combinations in a set of objects. Adds two complex numbers. Subtracts two complex numbers. Multiplies two complex numbers. Divides two complex numbers. Calculates the square root of a complex number. Determines the probability of s successes in n trials given a probability of p. Determines the cumulative probability of s or fewer successes in n trials given a probability of p. Calculates the probability density of a chi square distribution. Calculates the cumulative probability of a chi square distribution. Calculates the probability density of an F distribution. Calculates the cumulative probability of an F distribution. Calculates the probability density of a geometric distribution. Calculates the cumulative probability of a geometric distribution. Calculates the value at a given percent, mean, and standard deviation. If the mean and standard deviation are excluded, the distribution is assumed to be standard. Calculates the probability density under a normal distribution. If the mean and standard deviation are excluded, the distribution is assumed to be standard. Calculates the cumulative probability over a specified range under a normal distribution. If the mean and standard deviation are excluded, the distribution is assumed to be standard. Calculates the probability density of a Poisson distribution. Calculates the cumulative probability of a Poisson distribution. Calculates the probability density of a student t distribution. Calculates the cumulative probability of a student t distribution. Calculates the dot product of two vectors in i j k form. Calculates the cross product of two vectors in i j k form. Converts a vector in i j form to magnitude angle form. Converts a vector in i j k form to magnitude angle  angle form. Converts a vector in magnitude angle form to a vector in i j form. Converts a vector in magnitude angle  angle form to a vector in i j k form. 
Example
toDeg(pi/4) > 45 toRad(135) > 2.35619... sin(3) > 0.14112... cos(3) > 0.98999... tan(3) > 0.14254... csc(3) > 7.08616... sec(3) > 1.01010... cot(3) > 7.01525... sinh(3) > 10.01787... cosh(3) > 10.06766... tanh(3) > 0.99505... csch(3) > 0.09982... sech(3) > 0.09932... coth(3) > 1.00496... asin(0.5) > 0.52359... acos(0.5) > 1.04719... atan(0.5) > 0.46364... atanxy(0, 1) > 1.5707... acsc(3) > 0.33983... asec(3) > 1.23095... acot(3) > 0.32175... asinh(3) > 1.81844... acosh(3) > 1.76274... atanh(0.5) > 0.54930... acsch(3) > 0.32745... asech(0.5) > 1.31695... acoth(3) > 0.34657... abs(3) > 3 sqrt(9) > 3 exp(2) > 7.38905... e^2 > 7.38905... ln(e) > 1 log(100) > 2 logBase(81, 3) > 4 mod(17, 5) > 2 frac(1.34) > 0.34 rnd() > 0.8376276 (number will vary) sgn(3) > 1 gcf(15, 20) > 5 lcm(15, 20) > 60 bin(5) > 101 oct(35) > 43 hex(95) > 5F round(4.6) > 5 round(4.56, 1) > 4.6 int(4.1) > 5 fix(4.1) > 4 prime(4) > 7 fib(4) > 3 fact(4) > 24 nPk(5,3) > 60 nCk(5,3) > 10 iAdd(1, 0, 3, 2) > 4 + 2 i iSub(1, 0, 3, 2) > 2 + 2 i iMult(1, 0, 3, 2) > 3 + 0 i iDiv(1, 0, 3, 2) > 0.2307... + 0.1538... i iSqrt(9, 0) > 0 + 3 i binomPDF(10, 0.3, 3) > 0.266827932 binomCDF(10, 0.3, 3) > 0.6496107184 xsqPDF(0, 2) > 0.48860251190292 xsqCDF(2, 3, 9) > 0.027185847289986 fPDF(1.3, 2, 3) > 0.211626095398697 fCDF(1, 1.3, 2, 3) > 0.073198707443031 geometPDF(0.25, 3) > 0.140625 geometCDF(0.25, 3) > 0.578125 invNorm(0.6) > 0.253352956603448 invNorm(0.6, 5, 0.4) > 5.10134118264138 normalPDF(.7) > 0.312253933366761 normalPDF(6, 5, 1) > 0.241970724519143 normalCDF(0.2, 0.2) > 0.158519418878206 normalCDF(4, 6, 5, 1) > 0.682689492127269 poissonPDF(0.2, 3) > 0.001091641004104 poissonCDF(0.2, 3) > 0.999943159759242 tPDF(1.4, 2) > 0.125688153583681 tCDF(1.4, 2.4, 2) > 0.078257921761583 dot(1, 2, 3, 7, 8, 9) > 50 cross(1, 2, 3, 7, 8, 9) > 6i + 12j  6k toMagAng(1, 2) > 2.236... @ 1.107 rad toMagAngZ(1, 2, 3) > 3.741... @ 1.107... rad @ 0.640 rad toComp(3, 1.2) > 1.087...i + 2.796...j toCompZ(3, 1.2, 1) > 0.914...i + 2.352...j + 1.620...k 