Reverse Greek Conversion Golf Introduction

You must create a function to convert Greek numerals into Arabic numerals. The input will be a Greek numeral less than 1000 and more than 0. This is the reverse of my previous challenge.

Algorithm


Split input into letters (e.g. ΡΚΓ -> Ρ, Κ, Γ)
Take each letter, and change to character found in table below, for letter symbol, (e.g. ΡΚΓ -> Ρ, Κ, Γ -> 100, 20, 3).
Add (e.g. ΡΚΓ -> Ρ, Κ, Γ -> 100, 20, 3 -> 123)


Specifications


No built-in number-system conversion
Input will be capitalized as in example. 
Output must be in base 10.
ΡΡΡΡ will never happen. It will be Υ.


Test Cases

ΡΚΓ -&gt; 123
Η -&gt; 8
ΨΟΖ -&gt; 777
Ρ -&gt; 100
ΧϜ -&gt; 606
ΡϘ -&gt; 190
ΜΒ -&gt; 42
Ν -&gt; 50


Table

Α = 1 = Alpha = 913 UTF-8
Β = 2 = Beta = 914 UTF-8
Γ = 3 = Gamma = 915 UTF-8
Δ = 4 = Delta = 916 UTF-8
Ε = 5 = Epsilon = 917 UTF-8
Ϝ = 6 = DiGamma = 988 UTF-8
Ζ = 7 = Zeta = 918 UTF-8
Η = 8 = Eta = 919 UTF-8
Θ = 9 = Theta = 920 UTF-8

Ι = 10 = Iota = 921 UTF-8
Κ = 20 = Kappa = 922 UTF-8
Λ = 30 = Lambda = 923 UTF-8
Μ = 40 = Mu = 924 UTF-8
Ν = 50 = Nu = 925 UTF-8
Ξ = 60 = Xi = 926 UTF-8
Ο = 70 = Omicron = 927 UTF-8
Π = 80 = Pi = 928 UTF-8
Ϙ = 90 = Koppa = 984 UTF-8

Ρ = 100 = Rho = 929 UTF-8   
Σ = 200 = Sigma = 931 UTF-8
Τ = 300 = Tau = 932 UTF-8
Υ = 400 = Upsilon = 933 UTF-8
Φ = 500 = Phi = 934 UTF-8
Χ = 600 = Chi = 935 UTF-8
Ψ = 700 = Psi = 936 UTF-8
Ω = 800 = Omega = 937 UTF-8
Ϡ = 900 = SamPi = 992 UTF-8
Python 3, 112
Saved 4 bytes thanks to vaultah.
Booyah, beating JS!
lambda x,z=&quot;ΑΒΓΔΕϜΖΗΘΙΚΛΜΝΞΟΠϘΡΣΤΥΦΧΨΩϠ&quot;.find:sum((z(c)%9+1)*10**(z(c)//9)for c in x)

With test cases:
assert(f(&quot;ΡΚΓ&quot;)==123)
assert(f(&quot;Η&quot;)==8)
assert(f(&quot;ΨΟΖ&quot;)==777)
assert(f(&quot;Ρ&quot;)==100)
assert(f(&quot;ΧϜ&quot;)==606)

Loops through the string and uses its index in the list of potentials chars to calculate how much it's worth.