1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
|
use std::collections::HashMap;
use std::fmt;
pub struct Simulation {
history: Vec<Mortgage>,
updates: MortgageUpdates,
topay_total: f64,
topay_interest: f64,
payed_principal: f64,
payed_interest: f64,
payed_amortized: f64,
}
impl Simulation {
fn run(&mut self, mut mortgage: Mortgage) {
while mortgage.quotas > 0 && mortgage.principal > 0. {
self.history.push(mortgage.clone());
self.apply_updates(&mut mortgage);
self.payed_principal += mortgage.quota_principal();
self.payed_interest += mortgage.quota_interest();
mortgage.step();
}
}
fn apply_updates(&mut self, mortgage: &mut Mortgage) {
match self.updates.get_mut(&mortgage.period) {
Some(MortgageUpdate::Amortize(principal)) => {
if *principal > mortgage.principal {
*principal = mortgage.principal;
};
mortgage.principal -= *principal;
mortgage.monthly =
Mortgage::monthly(mortgage.principal, mortgage.i12, mortgage.quotas);
self.payed_amortized += *principal;
}
None => (),
}
}
pub fn render_table(&self) {
let mortgage = &self.history[0];
println!("\n========================================================");
println!(
"=== HIPOTECA: {}€, A {} AÑOS, INTERÉS FIJO {:.2}% ===",
mortgage.principal,
mortgage.quotas / 12,
mortgage.i12 * 12. * 100.,
);
println!("========================================================");
println!("\n\n# SIMULACIÓN CUOTAS\n");
println!("Year | Mon | Quota ( Intrst + Amrtzd) | Principal");
for mortgage in self.history.iter() {
print!("{mortgage}");
if let Some(update) = self.updates.get(&mortgage.period) {
print!(" {update}");
}
println!();
}
let payed_total = self.payed_principal + self.payed_interest + self.payed_amortized;
println!("\n\n# A PRIORI\n");
println!(
"== Total a pagar: {:.2} ({} cap + {:.2} int)",
self.topay_total, mortgage.principal, self.topay_interest
);
println!(
"== Los intereses suponen un {:.2}% del total",
100. * self.topay_interest / self.topay_total
);
println!("\n\n# RESULTADO FINAL\n");
println!(
"== Total pagado: {:.2} ({:.2} cap + {:.2} int + {:.2} amortizado)",
payed_total, self.payed_principal, self.payed_interest, self.payed_amortized
);
println!(
"== Los intereses suponen un {:.2}% del total",
100. * self.payed_interest / payed_total
);
println!();
}
}
#[derive(Clone)]
pub struct Mortgage {
period: u32,
principal: f64,
i12: f64,
monthly: f64,
quotas: u32,
}
impl fmt::Display for Mortgage {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
write!(
f,
"{:4} | {:3} | {:7.2} ({:7.2} + {:7.2}) | {:10.2}",
if self.period % 12 == 0 {
format!("Y{}", (self.period / 12) + 1)
} else {
// return Ok(());
"".to_string()
},
self.period,
self.monthly,
self.quota_interest(),
self.quota_principal(),
self.principal
)
}
}
impl Mortgage {
pub fn new(principal: f64, i1: f64, years: u32) -> Self {
let quotas = years * 12;
let i12 = i1 / 12.0;
Mortgage {
period: 0,
principal,
i12,
monthly: Self::monthly(principal, i12, quotas),
quotas,
}
}
pub fn simulate(&mut self, updates: MortgageUpdates) -> Simulation {
let topay_total = self.monthly * self.quotas as f64;
let mut sim = Simulation {
topay_total,
topay_interest: topay_total - self.principal,
payed_principal: 0.,
payed_interest: 0.,
payed_amortized: 0.,
history: vec![],
updates,
};
sim.run(self.clone());
sim
}
fn monthly(principal: f64, i12: f64, quotas: u32) -> f64 {
principal * i12 / (1.0 - (1.0 + i12).powi(-(quotas as i32)))
}
fn step(&mut self) {
self.period += 1;
self.quotas -= 1;
self.principal = (1.0 + self.i12) * self.principal - self.monthly;
}
fn quota_interest(&self) -> f64 {
self.i12 * self.principal
}
fn quota_principal(&self) -> f64 {
self.monthly - self.quota_interest()
}
}
pub type MortgageUpdates = HashMap<u32, MortgageUpdate>;
#[derive(Clone)]
pub enum MortgageUpdate {
Amortize(f64),
}
impl fmt::Display for MortgageUpdate {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
write!(f, "[MORTGAGE UPDATE: ")?;
match self {
Self::Amortize(principal) => {
write!(f, "{principal:.2} amortized to reduce quotas]")
}
}
}
}
|
